Verb TO DO is one of the most common verbs in the English language. It functions in various ways. Not only is it a helping verb, it’s a main verb as well.
The need for a helping verb is so necessary in the English language that when we want to figure a question out of a clause that doesn’t have one, we carry in a helping verb anyhow. And what helping verb do we use? That’s exact; it’s “do.
In the simple present tense, “to do” is conjugated as follows:
To do: the affirmative, negative and interrogative forms:
Affirmative forms of the verb to do:
Interrogative forms of the verb to have:
Negative Forms of the verb to have
Does Brad Pit speak Arabic?
No, he doesn’t. He speaks English.
What about Angelina Joli? Does she speak English, too?
Yes, she does.
No, They don’t.