三、語法與用法(16~20 題,請選擇最適當的選項 請選擇最適當的選項。)
【題組】16._____, you will find that people respect you more.
(A) If you did learn to keep your mouth shut
(B) If you can to learn to keep your mouth shut
(C) If you learn to keep your mouth shut
(D) If you might learn to keep your mouth shut