Match uppercase to lowercase
Games for Kids on Matching Lowercase and Uppercase Letters Online
Games for Kids on Matching Lowercase and Uppercase Letters Online - SplashLearnFilter
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- Matching Lowercase and Uppercase Letters (59)
- Match Aa - Dd (9)
- Match Ee - Gg (7)
- Match Hh - Kk (9)
- Match Ll - Pp (11)
- Match Qq - Ss (7)
- Match Tt - Vv (7)
- Match Ww - Zz (9)
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Match Aa - Dd Games for Kids (9)
View all 9 gamesMatch Aa - Dd
Find the Letters A, B, C & D Game
Put your language skills to the test by finding the letters A, B, C & D.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter A? Game
Kids must find the letter A to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter B? Game
Kids must find the letter B to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter C? Game
Kids must find the letter C to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg Games for Kids (7)
View all 7 gamesMatch Ee - Gg
Find the Letters E, F & G Game
Kids must find the letters E, F & G to play.
PREK K RF.
K.1.D
VIEW DETAILS
Match Ee - Gg
Can You Find the Letter E? Game
Kids must find the letter E to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Can You Find the Letter F? Game
Kids must find the letter F to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Can You Find the Letter G? Game
Kids must find the letter G to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk Games for Kids (9)
View all 9 gamesMatch Hh - Kk
Find the Letters H, I, J & K Game
Put your language skills to the test by finding the letters H, I, J & K.
PREK K RF.K.1.
D
VIEW DETAILS
Match Hh - Kk
Match Big and Small K Game
Put your language skills to the test by learning to match big and small K.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Can You Find the Letter H? Game
Kids must find the letter H to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Can You Find the Letter I? Game
Kids must find the letter I to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ll - Pp Games for Kids (11)
View all 11 gamesMatch Ll - Pp
Find the Letters L M, N, O & P Game
Put your language skills to the test by finding the letters L, M, N, O & P.
PREK K RF.
K.1.D
VIEW DETAILS
Match Ll - Pp
Match Uppercase and Lowercase O Game
Put your language skills to the test by learning to match big and small O.
PREK K RF.K.1.D
VIEW DETAILS
Match Ll - Pp
Match Uppercase and Lowercase P Game
Put your language skills to the test by learning to match big and small P.
PREK K RF.K.1.D
VIEW DETAILS
Match Ll - Pp
Can You Find the Letter L? Game
Kids must find the letter L to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Qq - Ss Games for Kids (7)
View all 7 gamesMatch Qq - Ss
Find the Letters Q, R & S Game
Kids must find the letters Q, R & S to play.
PREK K RF.
K.1.D
VIEW DETAILS
Match Qq - Ss
Can You Find the Letter Q? Game
Kids must find the letter Q to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Qq - Ss
Can You Find the Letter R? Game
Kids must find the letter R to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Qq - Ss
Can You Find the Letter S? Game
Kids must find the letter S to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Tt - Vv Games for Kids (7)
View all 7 gamesMatch Tt - Vv
Find the Letters T, U & V Game
Kids must find the letters T, U & V to play.
PREK K RF.K.1.D
VIEW DETAILS
Match Tt - Vv
Can You Find the Letter T? Game
Kids must find the letter T to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Tt - Vv
Can You Find the Letter U? Game
Kids must find the letter U to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Tt - Vv
Can You Find the Letter V? Game
Kids must find the letter V to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ww - Zz Games for Kids (9)
View all 9 gamesMatch Ww - Zz
Find the Letters W, X, Y & Z Game
Put your language skills to the test by finding the letters W, X, Y & Z.
PREK K RF.K.1.D
VIEW DETAILS
Match Ww - Zz
Match Uppercase and Lowercase Z Game
Put your language skills to the test by learning to match big and small Z.
PREK K RF.K.1.D
VIEW DETAILS
Match Ww - Zz
Can You Find the Letter W? Game
Kids must find the letter W to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ww - Zz
Can You Find the Letter X? Game
Kids must find the letter X to play this game.
PREK K RF.K.1.D
VIEW DETAILS
All Games for Kids on Matching Lowercase and Uppercase Letters
Match Aa - Dd
Find the Letters A, B, C & D Game
Put your language skills to the test by finding the letters A, B, C & D.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter A? Game
Kids must find the letter A to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter B? Game
Kids must find the letter B to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter C? Game
Kids must find the letter C to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter D? Game
Kids must find the letter D to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Time to Match A, B, C & D Game
Put your language skills to the test by learning to match A, B, C & D.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Revise the Letters: Big A, B & C Game
Revise the letters: Big A, B & C to practice your english skills!
PREK RF.
K.1.D
VIEW DETAILS
Match Aa - Dd
Revise the Letters: Small a, b & c Game
Revise the letters: Small a, b & c to practice your english skills!
PREK RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Find the Letters A, B, C & D Game
Put your language skills to the test by finding the letters A, B, C & D.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Match Big and Small D Game
Put your language skills to the test by learning to match big and small D.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter A? Game
Kids must find the letter A to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter B? Game
Kids must find the letter B to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter C? Game
Kids must find the letter C to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Can You Find the Letter D? Game
Kids must find the letter D to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Aa - Dd
Time to Match A, B, C & D Game
Put your language skills to the test by learning to match A, B, C & D.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Find the Letters E, F & G Game
Kids must find the letters E, F & G to play.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Can You Find the Letter E? Game
Kids must find the letter E to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Can You Find the Letter F? Game
Kids must find the letter F to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Can You Find the Letter G? Game
Kids must find the letter G to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Time to Match E, F & G Game
Put your language skills to the test by learning to match E, F & G.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Revise the Letters: Big D, E, F & G Game
Revise the letters: Big D, E, F & G to play this game.
PREK RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Revise the Letters: Small d, e, f & g Game
Revise the letters: Small d, e, f & g to play this game.
PREK RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Find the Letters E, F & G Game
Kids must find the letters E, F & G to play.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Can You Find the Letter E? Game
Kids must find the letter E to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Can You Find the Letter F? Game
Kids must find the letter F to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Can You Find the Letter G? Game
Kids must find the letter G to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ee - Gg
Time to Match E, F & G Game
Put your language skills to the test by learning to match E, F & G.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Find the Letters H, I, J & K Game
Put your language skills to the test by finding the letters H, I, J & K.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Match Big and Small K Game
Put your language skills to the test by learning to match big and small K.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Can You Find the Letter H? Game
Kids must find the letter H to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Can You Find the Letter I? Game
Kids must find the letter I to play this game.
PREK K RF.
K.1.D
VIEW DETAILS
Match Hh - Kk
Can You Find the Letter J? Game
Kids must find the letter J to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Can You Find the Letter K? Game
Kids must find the letter K to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Time to Match H, I, J & K Game
Put your language skills to the test by learning to match H, I, J & K.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Revise the Letters: Big H, I, J & K Game
Revise the letters: Big H, I, J & K to play this game.
PREK RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Revise the Letters: Small h, i, j & k Game
Revise the letters: Small h, i, j & k to play this game.
PREK RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Find the Letters H, I, J & K Game
Put your language skills to the test by finding the letters H, I, J & K.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Match Big and Small K Game
Put your language skills to the test by learning to match big and small K.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Can You Find the Letter H? Game
Kids must find the letter H to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Can You Find the Letter I? Game
Kids must find the letter I to play this game.
PREK K RF.
K.1.D
VIEW DETAILS
Match Hh - Kk
Can You Find the Letter J? Game
Kids must find the letter J to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Can You Find the Letter K? Game
Kids must find the letter K to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Hh - Kk
Time to Match H, I, J & K Game
Put your language skills to the test by learning to match H, I, J & K.
PREK K RF.K.1.D
VIEW DETAILS
Match Ll - Pp
Find the Letters L M, N, O & P Game
Put your language skills to the test by finding the letters L, M, N, O & P.
PREK K RF.K.1.D
VIEW DETAILS
Match Ll - Pp
Match Uppercase and Lowercase O Game
Put your language skills to the test by learning to match big and small O.
PREK K RF.K.1.D
VIEW DETAILS
Match Ll - Pp
Match Uppercase and Lowercase P Game
Put your language skills to the test by learning to match big and small P.
PREK K RF.K.1.D
VIEW DETAILS
Match Ll - Pp
Can You Find the Letter L? Game
Kids must find the letter L to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ll - Pp
Can You Find the Letter M? Game
Kids must find the letter M to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ll - Pp
Can You Find the Letter N? Game
Kids must find the letter N to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Ll - Pp
Can You Find the Letter O? Game
Kids must find the letter O to play this game.
PREK K RF.K.1.D
VIEW DETAILS
Match Qq - Ss
Find the Letters Q, R & S Game
Kids must find the letters Q, R & S to play.
PREK K RF.K.1.D
VIEW DETAILS
Match Tt - Vv
Find the Letters T, U & V Game
Kids must find the letters T, U & V to play.
PREK K RF.K.1.D
VIEW DETAILS
Match Ww - Zz
Find the Letters W, X, Y & Z Game
Put your language skills to the test by finding the letters W, X, Y & Z.
PREK K RF.K.1.D
VIEW DETAILS
Language learning comprises three crucial components – reading, writing, and spelling. Before kids get to this complex stage, they need to build their fundamentals.
This includes identifying letter names and sounds.
For children to identify and write down letters, they must be comfortable with uppercase and lowercase forms of all the letters in the alphabet. Some of them may be simpler since the upper and lowercase letters are almost alike. Take the letters P, O, and C as a case in point. Others may prove a little more complicated, like the letters A, B, and F.
With SplashLearn, you can help your child practice and improve their letter learning through games on matching the lowercase and uppercase letters.
Make PairsThe best way to help your kids learn the association is through pairing. Show them the upper and lowercase forms in random order and get them to form the correct pairs. By matching, a strong connection is formed between the letter patterns, making recall quicker and more effective.Odd One Out
In a series of assorted pairs, encourage your child to pick the mismatched pairs and set the sequence right.
This is a great way to check for understanding and recall. It also goes a long way in clarifying ideas.Think it ThroughYour kids are probably ready to recall the lower or uppercase letters of forms you show them. You can make this more fun by using clay, sand, water, or markers to help your children enjoy themselves and build their motor skills.Making a Strong Case
Forming associations and relations take a while. You will need to be patient and allow plenty of practice before your kids can showcase their learning. Using games and interactive techniques will produce better results and help your children enjoy themselves more. We bring you letter recognition and matching games for every vowel and consonant in the book. Do go through SplashLearn’s ELA resources for more.
Is there something we missed out on? Write to us at [email protected] with your feedback and comments. We would love to hear from you and enhance the learning experience for your kids.
Try SplashLearn for Free
Matching Uppercase and LowerCase Letters
This interactive and hands on game to teach matching uppercase and lowercase letters is a fun gross motor game for preschool and kindergarten. Use this interactive letter activity along as an alphabet matching with objects and a sensory-motor learning activity!
Matching uppercase letters to lowercase letters is a literacy task that supports reading skills, but also challenges visual discrimination skills, form constancy, and visual scanning, all of which are visual processing skills needed for handwriting and reading comprehension. What’s fun about this activity is that it builds these skills in a fun way!
Matching Uppercase and Lowercase Letters
Learning letters and matching upper and lower case letters is a Kindergarten skill that can be tricky for some kids. We made this easy prep letter identification activity using items you probably already have in the house.
If you’ve seen our blog posts over the last few days, you’ve noticed we’re on a learning theme using free (or mostly free) items you probably already have.
We’re sharing 31 days of learning at home with free materials this month along with 25 other bloggers in the 31 days of homeschooling tips series.
Today’s easy letter learning activity can use any letters you have around the house or magnetic letters and coffee filters.
While this activity is almost free if you’ve got the items at home already, we’re sharing the affiliate links for the items in this post.
How to play this interactive letter matching activity
You’ll need just a few items for this letter matching activity:
- Magnetic letters
- marker
- coffee filters (but paper towels or recycled paper would work as well.
To set up the activity, there are just a few steps:
- Grab the magnetic letters from the fridge and 26 coffee filters.
- Use a permanent marker to write one lower case letter of the alphabet on each coffee filter.
- With your child, match the magnetic letters to the lowercase letters on the coffee filters.
- Ask the child to help you crumble each letter inside the coffee filter that has its matching lowercase letter.
- Continue the play!
More ways to match uppercase and lowercase letters
By matching the magnetic uppercase letter to the lowercase letter on the coffee filter, kids get a chance to incorporate whole body movements and gross motor activity while looking for matching letters.
With your child, first match up each lower case coffee filter letter to the upper case magnetic letter.
You can spread the filters out to encourage visual scanning and involve movement in the activity, OR you can stack the coffee filters in a pile and one by one match up the letters. This technique requires the child to visually scan for the upper case magnet letters.
Try both ways for more upper/lower case letter practice!
We then wrapped the coffee filters around the magnets in a little bundle. There are so many games you can play with these upper and lower case letters:
- Match the same letter– match uppercase letters to uppercase letters and lowercase letters to lowercase letters.
- Alphabet matching with objects– Match an object that starts with the letter of the alphabet. Use small objects inside the coffee filter and match it to lowercase letters written in the coffee filter with uppercase magnet letters.
- Match the picture with the letter– Print off pictures of words that start with each letter of the alphabet. Then match the picture with letters of the alphabet using lowercase letters written on the filter and uppercase letters in magnetic letter form.
- Play a letter memory game– Hide letters around the room and challenge kids to find the letters in order to match the uppercase letter to the lowercase letters.
- Letter sound matching– Make a letter sound and challenge kids to find the letter that makes that sound.
- Letter Hide and Seek- Hide the bundled up letters around the room while your child hides his eyes. Send him off to find the letters and ask him to open the bundle and identify the letter.
- Letter Toss Activity- Toss the coffee filter bundles into a bucket or bin. Any letters that make it into the bin are winners!
- Name the letters- Unwrap the bundles and name the letters. Spread the coffee filters out around the room. Toss magnetic letters onto the matching lower case letter.
- Letter toss game- Toss a bean bag onto the coffee filters. The child can identify the lower case letter, then go to the pile of magnetic letters and find the matching upper case letter.
Can you think of any more ways to work on upper and lower case letter matching with coffee filters and magnetic letters?
Matching Big and Small Letters
The nice thing about this activity is that you can teach the concepts of big and small letters.
When we say “big letters” and “small letters”, we are showing the concept of letters that touch the top and bottom lines, or the upper case letters.
And teaching children the difference between those big letters and the small letters which touch just the middle point are part of the visual discrimination process that is needed for handwriting on the lines, or line awareness skills.
You will enjoy more alphabet posts from our archives:
- Hand-eye coordination letter match
- Building letters with baked cotton swabs
Looking for more interactive letter activities to match uppercase and lowercase letters? The Letters! Fine Motor Kit is for you!
Letter Kit for fine motor, visual motor, and sensory motor play.This 100 page printable packet includes everything you need for hands-on letter learning and multisensory handwriting!
This digital and printable packet includes these multisensory handwriting and letter formation materials:
- A-Z Multisensory Writing Pages
- Alphabet Fine Motor Clip Cards
- Cut and place Fine Motor Mazes
- A-Z Cotton Swab Cards
- A-Z Pattern Block Cards
- Fine Motor Letter Geo-Cards
- A-Z Color and Cut Letter Memory Cards
- Color By Size Sheets
- A-Z Building Block Cards
- A-Z Play Dough Letter Formation Cards
- Graded Lines Box Writing Sheets
- Alphabet Roll and Write Sheets
- Pencil Control Letter Scan
- Color and Cut Puzzles
Change case of text
Word for Microsoft 365 PowerPoint for Microsoft 365 Word for Microsoft 365 for Mac PowerPoint for Microsoft 365 for Mac Word for the web PowerPoint for the web Word 2021 PowerPoint 2021 Word 2021 for Mac PowerPoint 2021 for Mac Word 2019 PowerPoint 2019 Word 2019 for Mac PowerPoint 2019 for Mac Word 2016 PowerPoint 2016 Word 2016 for Mac PowerPoint 2016 for Mac Word 2013 PowerPoint 2013 Word 2010 PowerPoint 2010 Word 2007 PowerPoint 2007 Word Starter 2010 More.
..Less
You can change the case of selected text in a document by clicking the Change case button on the Home tab .
Note: For autocapitalization rules, see Autocorrect settings: Capitalization, spelling, and symbols.
Change case
To change the case of selected text in a document:
-
Select the text whose case you want to change.
-
Navigate to home > change .
-
Do one of the following:
-
To capitalize the first letter of the application and leave the rest in lowercase, select As in sentences .
-
To make all letters lowercase, select all lowercase .
-
To capitalize all letters, select option ALL CAPS .
-
To capitalize the first letter of each word and lowercase the rest, select Start In Uppercase .
-
To reverse case (for example, switch from mode Start Capitals to mode START WITH LOWER ), select CHANGE CASE .
Tips:
-
To apply small caps to text, select the text, and then on the Home tab , in the Font group, click the arrow in the lower right corner. In dialog box Font in section Modification check box small caps .
-
To undo a case change, press CTRL+Z.
-
To use keyboard shortcuts to change case, upper case, and upper case in each word, select the text and press SHIFT+F3 until the correct case is applied.
-
See also
Insert a drop cap
AutoCorrect Setting: Capitalization
Case change
To change the case of selected text in a document:
-
Select the text whose case you want to change.
-
Navigate to home > change .
-
Do one of the following:
-
To capitalize the first letter of the application and leave the rest in lowercase, select As in sentences .
-
To make all letters lowercase, select all lowercase .
-
To capitalize all letters, select ALL CAPITAL .
-
To capitalize the first letter of each word and lowercase the rest, select Start In Uppercase .
-
To reverse case (for example, switch from Start CAPS to START LOCK mode), select CHANGE CASE .
Tips:
-
To apply small letters to text, you select the text, and then on the Format menu, choose Font , and then in the Font dialog box, in the Effects area, select the Small Letters box.
Small Caps shortcut key : ⌘ +SHIFT+K
-
To undo a case change, press ⌘ +Z.
-
To use keyboard shortcuts to change the case, uppercase, and case of each word, select the text and press FN+SHIFT+F3 until the desired style is applied.
-
See also
Insert a drop cap
AutoCorrect Setting: Capitalization
PowerPoint for the web supports dossier editing. See procedure below.
Word for the web does not support editing a case.
Open a document in the desktop app and edit its dossier. Alternatively, you can manually change the casing text in Word for the web.
-
Select the text you want to change.
-
Navigate to home > Additional font options > Change file .
-
Select the desired register.
Uppercase and Lowercase Letters / Habr
I have gathered here some not-so-obvious facts about uppercase and lowercase letters that a programmer may encounter in their work.
Many of you have translated strings into "all uppercase" (uppercase), "all lowercase" (lowercase), "first capital, and the rest lowercase" (titlecase). Even more popular is the case-insensitive comparison operation. On a global scale, such operations can be quite non-trivial. The post is structured as a "collection of misconceptions" with counterexamples.
1. If I convert the string to uppercase or lowercase, the number of Unicode characters does not change.
No. The text may contain lowercase ligatures, which do not correspond to one character in upper case. For example, when translating to uppercase: fi (U+FB00) -> FI (U+0046, U+0049)
2. Ligatures are a perversion, no one uses them. If they are not taken into account, then I'm right.
No. Some letters with diacritics do not have an exact match in other case, so you have to use a combined character. Let's say the Afrikaans language has the letter ʼn (U+0149).
In upper case, it corresponds to a combination of two characters: (U+02BC, U+004E). If you come across a transliteration of Arabic text, you may encounter (U+1E96), which also does not have a single-character match in upper case, so you will have to replace it with (U+0048, U+0331). The Wakhi language has a letter (U+01F0) with a similar problem. You may argue that this is exotic, but there are 23,000 articles in Afrikaans on Wikipedia.
3. All right, but let's consider a combined character (involving modifying or combining code points) as one character. Then the length will still be preserved.
No. There is, for example, the letter "escet" ß (U+00DF) in German. When converted to uppercase, it turns into two SS characters (U+0053, U+0053).
4. Okay, okay, got it. We will assume that the number of Unicode characters can increase, but not more than twice.
No. There are specific Greek letters, for example, (U+0390) that turn into three Unicode characters (U+0399, U+0308, U+0301)
5.
Let's talk about titlecase. Everything is simple here: I took the first character from the word, translated it into uppercase, took all the subsequent ones, translated it into lowercase. No. Let's remember the same ligatures. If a word in lowercase begins with fl (U+FB02), then in uppercase the ligature becomes FL (U+0046, U+004C), but in titlecase it becomes Fl (U+0046, U+006C). The same with ß, but, theoretically, words cannot begin with it.
6. Those ligatures again! Well, we take the first character from the word, translate it into uppercase, if more than one character is obtained, then we leave the first one, and the rest back into lowercase. Then it will definitely work.
Won't work. There is, for example, the digraph dz (U+01F3), which can be used in text in Polish, Slovak, Macedonian or Hungarian. In uppercase it corresponds to the digraph DZ (U+01F1), and in titlecase it corresponds to the digraph Dz (U+01F2).
There are other digraphs. The Greek language, on the other hand, will please you with jokes with hypogegrammen and progegrammen (fortunately, this is rarely found in modern texts). In general, the uppercase and titlecase variants for a character can be different, and there are separate entries for them in the Unicode standard.
7. Good, but at least the result of converting a character's case to uppercase or lowercase does not depend on its position in the word.
No. For example, the Greek capital sigma Σ (U+03A3) becomes a lowercase ς (U+03C2) at the end of a word and σ (U+03C3) in the middle.
8. Oh, okay, let's process the Greek sigma separately. But in any case, the same character in the same position in the text is converted in the same way.
No. For example, in most Latin languages, the lower case for I (U+0049) is i (U+0069), but not in Turkish and Azeri. There, the lower case for I is ı (U+0131) and the capital case for i is İ (U+0130).
In Turkey, because of this, enchanting bugs are sometimes observed in a variety of software. And if you come across a text in Lithuanian with accents, then, for example, a capital Ì (U + 00CC), which will turn not into ì (U + 00EC), but into (U + 0069, U + 0307, U + 0300) . In general, the result of the conversion also depends on the language. Most of the complex cases are described here.
9. What a horror! Well, let's now correctly convert to uppercase and lowercase. Comparing two words case-insensitively is not a problem: we translate both into lowercase and compare.
There are also many pitfalls that follow from the above. For example, it will not work with German straße and STRASSE (the former will not change, the latter will turn into strasse). There will also be problems with many of the other letters described above.
10. M-yes… Maybe then everything is in the uppercase?
And it won't always work (although much more often).
