I'm afraid this painting is not by Picasso. It's only a copy and so it's _____.
| A．priceless | B．invaluable | C．unworthy | D．worthless |
It seemed selfish __________ them anything.
| A．for him not give | B．of him not give |
| C．for him not to give | D．of him not to give |
It's necessary __________ the car when you do not use it.
| A．of you to lock | B．for you locking |
| C．for you to lock | D．for you to be locked |
I found it __________ the purport of his speech.
| A．was difficult to understand |
| B．difficult to understand |
| C．difficult understand |
| D．both A and B |
The person is very nice __________.
| A．to work with | B．to work |
| C．to be worked | D．to be worked with |
You are so __________ your car.
| A．silly not have locked |
| B．silly not to have lock |
| C．silly not to have locked |
| D．silly not to lock |