I’mnotgoodatMaths,soIdon’tknow

問題詳情：

I’m not good at Maths, so I don’t know _________ out this difficult Maths problem.

A. when to work    B. who to work      C. what to work      D. how to work

【回答】

D

知識點：非謂語動詞

題型：選擇題