Question

Which of the following is a subordinate adverb? Select all that apply.
a:if
b:after
c:therefore
d:whenever

Answer 1

c & d i am pretty sure of this 

Answer 2

Answer: If, after and whenever.

Explanation: Although the word after can also be used as a preposition ("We ate dinner after the game") or a conjunctive adverb ("We first played the game. After, we had dinner"), you can also start a subordinating adverb clause with it ("After we played the gamed, we had dinner"). If and whenever are frequent subordinate adverbs. Therefore can only be used as a conjunctive adverb ("We won the game. Therefore, we ate dinner at our favorite place.")