Do-support

English speakers use the words "do", "does," and "did" as auxiliary (helper) verbs, to form questions, or to reply to questions or for emphasis.

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see Do-support - Wikipedia

"Do-support "Interrogatories

Did you do your homework?

Do you have

Do-support "pro-verbs"

"pro-verb" is a verb that acts for ("pro-") another verb

like a pronoun, it is used to avoid repetition of the verb

• Go carefully as I do
• Who ate the cookies? I did
• She doesn't like that movie, but I do
  • note that "can" and "will" also act like pro-verbs
    • She can't figure it out, but I can
    • He can't go, but I will.