提示：句意："他很少在学校吃饭，是吗？"seldom构成的句子为否定句，反意问句应用肯定形式。

答案：D

6.（经典回放）I won't let you in________you show me the written permission of the commander.

A.apart from B.unless

C.except D.but

提示：句意："除非你给我看你长官的书面允许，否则我不能让你进去。"而A、C、D三项都是介词。

答案：B

7.（经典回放）Sandy could do nothing but ________to his teacher that he was wrong.

A.admit B.admitted

C.admitting D.to admit

提示：句意："她除了向老师承认她错了，别无办法。"could do nothing but do"除......之外不能做某事。"

答案：A

8.（经典回放）I know nothing about the young lady ________she is from Beijing.

A.except B.except for

C.except that D.besides

提示：句意："对于这个年轻女人，我除了知道她来自北京之外，别的一无所知。"A、B、D三项均为介词后不加句子。

答案：C