It's really very dangerous.One more step，________ the baby will fall into the well.
| A．or | B．so | C．but | D．and |
In this university a medal with ten thousand dollars ________gains success in science and technology every two years .
| A．is given to whoever | B．are given to anyone who | C．gives to whomever | D．give to everyone |
— Thank you for your CD - ROM. I'll return it as soon as I can. — ________. I've got another one to spare.
| A．No problem | B．No hurry | C．With pleasure | D．Nothing much |
Apples are usually sold by ________ weight and eggs are sometimes sold by ________ dozen.
| A．the; the | B．/;a | C．/; the | D．the; a |
Although punctual himself, the professor was quite used ________ late for his lecture.
| A．to have students | B．for students' being | C．for students to be | D．to students' being |
.When people move to another country, they often try ________ the customs of their native land.
| A．to keep on | B．to keep off | C．to keep up | D．keeping up |