问题

______ of years later, the first extremely small plants began to appear on the surface of the water.

A:millions
B:million
C:million of
D:millions of;

正确答案是：

同类题型

In my opinion, hard work is as important as, ______ an efficient way in study. [ ]

re determined to go into the dark cave, ______my warning of danger

His grandparents live in a small house, but they don’t feel .

Where are my model planes, mom—–Sorry, I don’t know. Oh, look, they are_________.

The student sat there, __________ what to do. [ ]