Question

fix any punctuation or capitalization errors below. click \submit answer\ if there are none.
captain america decided to buy a rosemary plant; since he uses the herb all the time in his cooking.

Explanation:

The original sentence uses a semicolon before a subordinate clause introduced by "since", which is incorrect. A semicolon is used to separate two independent clauses, but "since he uses the herb all the time in his cooking" is a dependent clause. So we should replace the semicolon with a comma.

Answer:

Captain America decided to buy a rosemary plant, since he uses the herb all the time in his cooking.