What are the three unilateral y positions of verbs? For example, study --- syudies, urgent The more, the better

What are the three unilateral y positions of verbs? For example, study --- syudies, urgent The more, the better

tidy-tidies

What are the verbs to y + ies

carry,study

Why do some words with y at the end need to remove y and add ies, while some words don't
For example: when body becomes plural, it is bodies, and when body becomes plural, it is bodies

1. When a noun ending with "consonant + Y" becomes plural, first change y to I and then add - es
baby-babies city-cities
Another example: body, party, story, family, country, factory, library, dictionary, etc
2. When the action verb ending with "consonant + Y" changes to the third person singular, first change y to I and then add - es
study-studies carry-carries
Another example: copy, worry, cry, cry, fly, spy, etc
3. When some adjectives ending with "consonant + Y" change to comparative and superlative, first change y to I, then add - er or - est
busy-busier-busiest
Early earlier earliest
Another example: easy, happy, heavy, healthy, angry, hungry, dirty, tidy, thirsty, lazy, noisy and so on
4. When some adjectives ending with "consonant letter + Y" change into adverbs, first change y into I, then add - ly
easy-easily lucky-luckily
angry-angrily happy-happily
heavy-heavily noisy-noisily
5. When the action verb ending with "consonant + Y" becomes the past tense or past participle (only limited to rule change), first change y into I and then add - ed
study-studied tidy-tidied
copy-copied
Another example is: carry, cry, try, spy, etc
6. When a few verbs ending with "consonant + Y" become adjectives, they need to add the suffix - ed. at this time, they first change y into I, and then add - ed
worry-worried fry-fried
7. The cardinal number is changed into an ordinal number, and eight "integral tens" end with - ty, change y into ie, and then add - th
twenty-twentieth thirty-thirtieth
forty-fortieth fifty-fiftieth
sixty-sixtieth seventy-seventieth
eighty-eightieth ninety-ninetieth
The above seven cases have one common feature, that is, first change y to I, then add the suffix. Another case, only a few words, but "the opposite way", first change ie to y, then add - ing
Lie lying lie lying lie lying lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie lie
Tie tying