问题

If we throw away too much waste and can’t keep good ecosystem,we _________ our future.

A:must have destroyed
B:could be destroying 
C:may be destroying
D:must destroy 

正确答案是：

同类题型

What do you think about robbers in the book, Kitty–

Oh, my God! We have missed the last bus. What shallwe do—I’m afraid we have no ________ but to take a taxi.

Two-fifths of the highway________so far.

The boy was so careless that the glass fell from his hand and it ______ on the floor.

How long ago _________ you _________ the English Club—I _________ it since two years ago.