Question

We are wondering ________ we can prevent people from polluting the earth.

A．who

B．that

C．whether

D．what

Answer 1

C

考查引導詞。句意“我們想知道我們能否阻止人們污染地球。”who“誰”；that引導賓語從句，無意義；whether“是否”；what“什么”。故選C。