单选题 (一共5题,共5分)

1.

Listen! Our science teacher _____the use of the robot.

2.

Ann has got a letter from her best fiend. It makes ___ quite excited.

3.

The villagers plan _____a new bridge over the river.

4.

A lot of trees _____in our city in spring every year.

5.

Protecting ourselves is one of _____ things we must do