It is good manners to eat upis left in your plate.A. thatB. whatC. whichD. all

问题补充：

It is good manners to eat upis left in your plate.

A. that

B. what

C. which

D. all

答案：

A. that

(答案→)B. what

C. which

D. all

解析：考查从句，从句is left in your plate缺少主语，which和what都可以做主语，但是what表示…东西，所以选B，句子意思“把盘子剩下的东西全吃完是个好习惯”