"I had John return the video": why do we use "return" instead of "returns" or "returned"?

Solution 1:

This sentence is an example of an indirect command or request. Such sentences are considered by some grammarians to be an example of the subjunctive, which in this case appears as the verb itself. (This is what I was taught in grade school.)

Others (see comments) argue that this need not be classified as subjunctive, but rather as a use of the infinitive:

... we would use him in the same construction: I had him return the video for me. This means there is no subordinate clause with omitted that (*I had [that] he return the video), but rather a simple object (him) + infinitive (return). The fact that you can't add that supports the same conclusion. — Cerberus.

Whatever the explanation, this usage is not dependent on the tense of the main verb of the sentence, which can be future, past or present.

Other examples of indirect commands:

His mother demanded he be home by 12. (Past)

The doctor has patients provide a detailed medical history. (Present)

Henry will insist we come early to the party. (Future)

Solution 2:

It is because, Emie, this construction requires the non-finite form of the verb, return, and non-finite forms don't inflect for tense or number or person.

Solution 3:

That is because return is an infinitive:

• I had John return the video for me.
• I had him return the video for me.

If you substitute him, it becomes clearer that this is a simple main clause with an object him. (The object functions as the thematic patient of the finite verb had and as the agent of the infinitive return.) There is no particular reason that I know of why the verb to have should use this construction when it means you are causing someone to do something. Perhaps one can be dug up from pre-modern usage.

The same construction is used with similar verbs:

• I had him return the video for me.
• I made him return the video for me.
• I bade him return the video for me. — Old fasioned.
• I told him to return the video for me.
• I caused him to return the video for me.
• I forced him to return the video for me.

With the verbs to tell, to cause, and to force, you can see that the infinitive with to is used instead of the bare infinitive. I don't see how this construction could be interpreted differently. If it had been a subjunctive, he would have been used instead of him, because there would be a subordinate clause with omitted that:

*I had [that] he return the video for me.

This is plainly ungrammatical.

Solution 4:

Return is the command form of return. E.g. "Return that which you have taken from me!"

When you have someone return something, you are implicitly using a command. This is because I had him X is synonymous to I required him to fulfil the command that he X.