This question already has an answer here:
- Pants — “is it” or “are they”? 2 answers
Since 'pants' is one of those always plural words, I can't figure out which sounds right.
My dup-close vote was miscast, so let me make amends by supplying an answer. That said, I feel like this is actually General Reference, and far too simple for this site. It’s part of the fundamental mechanics of how numeric concordance between subject and verb works, and it is hardly limited to English alone. This is a very, very common feature of many languages.
The bottom line is that word order does not matter. The grammatical number of the subject dictates the grammatical number of that subject’s verb. The subject of the sentence is not pants but he.
Because you would always say
in just the same fashion, you must therefore ask
because the subject is he and thus the corresponding verb must be singular.
This is just like how when you rearrange this sentence:
That the new proximity of streets to the verb has no effect whatsoever upon the number of that verb, because streets is still not the subject. Boy is.
Just because purses is near the verb does not change the number of that verb, since its subject is actually the singular woman rather than the plural purses.