1.The girl in white must be a nurse,_?
a.isn't she
b.mustn't she
c.may not she
d.didn't she
答案是a,为什么不是b?
2.This exercise is__difficult_____.
a.so;that few of us can do
b.so;that few of us can do it
c.too;for anyone of us to do
d.too'for anyone of us to do it
答案是b我选a,为什么要接it?顺便解释下什么叫复合句