---How amazing it is that astronauts are exploring outer space!
----- It’s a challenge, I guess, man against nature.
| A．of | B．for | C．by | D．about |
—What about 100 yuan? That’s my final offer.
—_______ I sell it to you just at the cost price this time for your future visit to my shop.
| A．You win. | B．What for? |
| C．No comment. | D．Out of the question. |
—Will you go to Mary’s wedding party tonight?
—I’m afraid not. I _______ my brother’s.
| A．will attend | B．have attended |
| C．am attending | D．will be attending |
Lacking _______ evidence, the police couldn’t arrest the man.
| A．ordinary | B．potential |
| C．solid | D．common |
A kind passenger paid for my ticket, without which I _______ the last train.
| A．couldn’t catch | B．couldn’t have caught |
| C．didn’t catch | D．hadn’t caught |
—I have done well in the exam because of no careless mistakes.
—Congratulations! Students can never be _______ careful in exams.
| A．so | B．very | C．too | D．enough |