There are______ living things on the earth. We must value our home—the earth.A. millions B. million of C. millions of
Only after a year ______ to see the results of my work.
My family like to travel. Mother prefers to take a bus to travel, while father ______ to travel.
We'll never give up working on the experiment (实验), ______ difficult it is.
After class, students ______ clean the chalk off the blackboard.
The fish on the table ______. I want to eat it right now.