The old man asked Lucy to move to another chair _______ he wanted to sit next to his wife.
| A．although | B．because | C．unless | D．if |
As we know, too much ________ to Xrays can cause skin burns, cancer or other damage to the body.
| A．contact | B．appeal |
| C．exposure | D．contribution |
The lesson Mr Li gave just now was too difficult for the class to ________.
| A．take up | B．take out |
| C．take down | D．take in |
The scientists recommend that studies ________ to find out what side effects the medicine might cause.
| A．be done | B．should do |
| C．will be done | D．are done |
An advertisement is useful in ________ it lets customers know of the kinds of goods in the shops.
| A．that | B．which | C．what | D．whether |
—I need some fresh air, so I am going out for a walk.
—________.
| A．You'd better not | B．Have fun |
| C．With pleasure | D．I sure am |