You should understand the traffic role by now. You've had it __________ often enough.
| A．explaining |
| B．to explain |
| C．explain |
| D．explained |
Neither I nor Jane and Marytired of having one examination after another.
| A．is | B．are | C．am | D．be |
you talk to someone or write a message，you show your skills to others.
| A．At times | B．Some time | C．Every time | D．The time |
It seemed that the water.
| A．was to blame | B．was to be blamed | C．should blame | D．was blamed |
He became inspired when he thought about helping ordinary peopleto cholera.
| A．expose | B．exposed | C．exposing | D．to expose |
—Dock doesn't know much about computers.
—.
| A．So he did | B．So does Mary | C．Neither do I | D．Nor will Mary |