—I’mbusywithmyschoolworkthesedays.  —That’sgreat!Youwo...

問題詳情：

 —I’m busy with my schoolwork these days.

   —That’s great! You won’t get good grades ______ you work hard.

A. if      use         C. unless        D. after

【回答】

C

知識點：連詞

題型：選擇題