It depends on what kind of question eg:
present simple - Where do you live. verb do = the base form.
past simple - Where did you live last year. verb is did = past tense form of do.
present continuous - What are you doing after lunch. verb is doing = present participle form of do.
present perfect - What have you done with the keys. verb is done = past participle form of do.
For yes/no questions the verb could be a be verb - Areyou happy. verb is are = plural present form of be.
(I have not put question marks in the questions because sometime wiki answers does not like answers with questions in them).
The sentence "May you borrow this" is an example of an interrogative sentence, specifically a polite request or permission seeking question. It is structured as a question with the modal "may" as the helping verb.
Treated is a regular verb.
"Do" is a verb when used in a question as a helping verb helping to form the interrogative structure.
"Is" is the verb. There is no adverb in the question.
"Spoke" is a verb in the past tense form. It is the simple past tense of the verb "speak."
If you, at the beginning of such a question, put your why and verb at the end, then your question would look like this: Why at the beginning a verb in question do you have to put?
"Caught" is the past tense of "Catch" which is an irregular verb. I hope this answers your question.
A linking verb
A linking verb.
It is an irregular verb.
The verb appear can be a linking verb or an action verb.
An auxiliary verb
the infinative
a regular verb.
Is becomes a verb
It is a regular verb
Be is a state of being verb.