问题

There is no doubt _____ humans should protect the environment.
A:that
B:which
C:what
D:why;
B:which
C:what
D:why;
正确答案是:
同类题型
I knocked into a tree when I went to the bus stop formy friend.—I suppose you _____too fast.
_by the noise, they had to finish themeeting early
Everyone doesn’t agree to the plan Some support itwhile I’m one of ______ opposed to it
His mother doesn’t allow him____computer games any more.
Look! Sonia looks worried. There must be ________ wrong with her.