(1)                        (2)                      (3)

1. There are many ______ in the old house.

2. I often go to Beijing by ______ with my father.

3. Before you go online,  you must connect the ______ to the computer.

4. Our teacher often ______ (检查) our homework in class.

5. The doctor ______ (挽救) many people's lives every year.