What is the subject and verb for this sentence - When he ran, the boy lost his breath.

Well, technically, there are two of each as shown below.

Explanation:

he + ran

boy + lost

If you had to choose only ONE pair as the answer, then go with "boy + lost" because they are contained in the main (independent) clause of the entire sentence. The entire sentence is actually a complex sentence because it is composed of a dependent (subordinating) clause + an independent (main) clause.

Does that make sense?

Answer: Boy (subject), Ran (Verb)

Explanation:

Because a subject is a person, place, thing, or idea. And the boy is a person so therfore he is the subject. The verb is an action. So when it says the boy ran what is he doing, running. So therfore ran is the verb.