Uses of Do

ESL learners sometimes have difficulty with the uses of the verb do. For example, a reader wonders about the use of the -ing form doing:

According to what I have learned, “do” is used with the simple present form of the verb to make a question: “Do you like pizza?” But I have seen “do” used with the “-ing” form of the verb:

“Does closing a scheme for new money pay off?”
“Does shutting furnace vents improve efficiency?”
“Does doing a tattoo hurt?”

Please explain.

Do may be used as either a main verb or as a helping verb. Its forms are do, did, (have) done, doing.

As a main verb, do means “to carry out some action.”

What shall I do about the spoiled fruit? (main verb)
Mr. Baxter does odd jobs. (main verb)
She did all the cleaning for her mother. (main verb)

As a helping verb, do is used to pose questions:

Do you live in the neighborhood? (The main verb is “do live.”)
Does your dog know the basic commands? (The main verb is “does know.”)
Didn’t I see you at the Court House yesterday? (The main verb is “did see.”

Do is used both to frame a negative statement and to contradict a negative statement:

A: I don’t think you know Charley. (negative statement)
B: I do know him. (contradiction)

A: I don’t think Mrs. Wong turned off the lights last night. (negative statement)
B: She did turn them off. (contradiction)

Do is used for emphasis:

I do love chocolate chip cookies!
Jack certainly does love his Monday night football!

The form doing can be used with a helping verb to form a main verb, as in “She was doing her best not to cry,” but in the examples that puzzle the reader, the -ing form doing is not part of the verb. It is a noun (gerund):

Does closing a scheme for new money pay off? (The verb is “does pay off.” The subject is “closing a scheme for new money.”)

Does shutting furnace vents improve efficiency? (The verb is “does improve.” The subject is “shutting furnace vents.”)

Does doing a tattoo hurt? (The verb is “does hurt.” The subject is “doing a tattoo.”

In some contexts, the verb do cannot be replaced. For example, “What shall I do?” But in many others, it can be replaced by a more specific verb. For example, “I’m doing the dishes” can be rephrased as “I’m washing the dishes.”

Here are some common expressions that use do as a main verb:

do a favor
do well/do badly
do good/do evil
do damage
do homework
do housework
do nothing
do research
do something
do the math
do one’s best
do 70 miles an hour
do time (serve a prison sentence)