What is the verb be?

In the case of the main system table, the copula is brought forward directly, except I am
When does appear, the third person singular predicate verb should change its prototype
The verb be is am are

RELATED INFORMATIONS

1. When do you start with the verb be and when do you use the auxiliary verb? Why do some sentences use do or does, and sometimes is / are? Is there a verb in a general question, that is, an auxiliary verb? Do you Why not use are you.
2. What is the difference between auxiliary verb and be verb in general questions?
3. What auxiliary verb is used to ask questions in special questions and what be verb is used to ask questions? For example, where did you go on vocation
4. When to use auxiliary verbs and be verbs in special questions For example, where do you live? Why not say where are you live?
5. When to use auxiliary verbs and be verbs in English interrogative sentences For example, are you a student? Can it be written as do you a student? Do you like apples? Are you like apples? If not, say the reason, and how to judge such questions
6. In the present continuous tense, what kind of verb needs double ending and ing?
7. When does the verb double write and add ing emergency
8. What is the adverbial of time in the present continuous tense? The more the better, the better
9. What is the adverbial of time in the present continuous tense
10. The problem of the adverbial of time, He is sweeping the floor According to the literal meaning, do you need to add time adverbial after it, now.at the monent.right Now If you add the literal meaning, will it change? Or can you add it or not? Are you emptying that bottle? Are you emptying the castle or are you emptying this castle?
11. How to change a general question,
12. What is the be verb in interrogative sentences I always thought it was linking verb But today I read the grammar book published by Pearson. It says that it is helping verb·· Is that so? Is the be verb in declarative sentences such as I am a student linking verb? Oh, that means there should be no copulars in interrogative sentences~
13. When the be verb in a declarative sentence is a notional verb, how to change it into a general question or a special question? Please explain Tom is (smart almost 1.75 meters) Wrong. Tom is (smart, almost 1.75 meters.) asking questions in brackets
14. The difference between be interrogative sentence and general interrogative sentence Are you speak chinese? Do you speak chinese? What's the difference? It means the same Why is it wrong
15. How many kinds of progressive tense are there in all
16. Is it suitable for negative sentences and interrogative sentences
17. In which interrogative sentence should the verb be reduced Please give some examples at the beginning of "does, can" and "special questions" to explain in which sentence the verb should be restored,
18. How do verbs change in interrogative and negative sentences?
19. How do verbs change in interrogative sentences and negative sentences Do the verbs in interrogative sentences and negative sentences basically change into their original forms? (excluding special cases) Or according to the tense of the sentence? Do you keep the verbs in their original form when you use do and does?
20. When do interrogative sentences and negative sentences return to their original forms I want to know under what tense the verbs in interrogative and negative sentences are restored to their original forms? Under what tense do verbs in interrogative and negative sentences need not be restored Which words must be followed by the original verb form?