1. How to form a third person singular?
And nouns from singular to plural law is roughly the same, namely:
(1) is generally composed of verbs followed by -s: work/works, read/reads, etc.
(2) Verbs with the structure of S, X, Z, sh, ch and the letter O, followed by -es:guess/guess, mix/mixes, go/goes, buzz/buzzes, finish/finishes, catch/catches, etc.
(3) Verbs ending in consonants plus Y should be changed from Y to I plus -es:fly/ fly, study/ learning, etc.
Note ① There are some irregular changes, such as have/has, be/is, etc.
② The pronunciation rules of suffixes -s and -es are: after S, X, Z, sh and ch, ES is pronounced as [iz], and the rest are pronounced as [z].
2. How to form past tense and past participle
There are two kinds of regular changes and irregular changes. Irregular changes need to be memorized one by one, and regular changes follow the following principles:
(1) Generally, verbs consist of ed: work/worked, stay/stay, shot/shot, etc.
(2) Only add D:close/ closed, like/ like, live/ live, smile/ laugh after verbs ending in-e. ..
(3) Verbs ending with consonants plus Y should be changed from Y to I plus -ed:study/ learned, carry/ carried, etc.
(4) Verbs ending in stressed closed syllables or R syllables with only one consonant at the end should be written as -ed: stop/stopped, admit/admissed, refer/refered, preferred/preferred, etc.
Note (1) For verbs ending in the letter L, if the last syllable is stressed, it must be written with -ed, such as control/controlled, but if the last syllable is not stressed, it can be written with L (British English) or without L (American English), such as travel/travel(l)ed.
(2) The past tense and past participle of the verb picnic is a picnic, not a picnic.
(3) The pronunciation rules of the suffix -ed are: pronounced as [t] after the consonant is clear, [d] after the vowel voiced consonant, and [id] after the consonant [t] or [d].
3. How to form the present participle
(1) In general, -ing is added after verbs: work/work, sleep/sleep, wait/wait, etc.
(2) Add: smile/smile, move/move, etc. After removing e from the verb ending in e.
(3) Verbs ending in stressed closed syllables or R syllables with only one consonant at the end should be written as -ing:sit/ sit, plan/ plan, refer/ reference, occurrence/ occurrence, etc.
(4) Verbs ending in the letter ie generally change ie to Y, and then add ING:Die/ dying, Lie/ lying, Tie/ tying, etc.
Pay attention to (1) verbs ending in the letter L. If the last syllable is stressed, you must double write L and then add ing, such as control/controlling, but if the last syllable is not stressed, you can double write L (British English) or not double write L (American English), such as travel/travel(l)ing.
(2) Nouns are plural, adjectives and adverbs are comparative and superlative, verbs are past tense, and past participles have "Y-changing rules", but present participles of verbs have no "Y-changing rules".
(3) The present participle of the verb picnic is picnic, not picnic.