Lucy didn’t make mistakes in the math exam. She is _____ in my class.

-Do you like the film? --Yes, I do. In fact, I’ve never seen a           one.      

-----Why do many people like to ride bikes?----Because bikes not only need ________ space, but also cause _________accidents.

This lesson is         that one.

The world’s population is growing ______ and there is _______ land and water for growing rice.