I haven’t heard from Bill ________ he left here.

A．when                                B．before

C．since                                 D．while

We humans are only born with one set of eyes, so it's our job to take care of them for our whole lives. The good news is that if we do a few simple things every day, we can maintain (保持) our eyesight and reduce (减少) the risk of ever hurting our eyes.
Almost all doctors agree that we can improve and maintain good eyesight by eating lots of fresh fruits and vegetables. It is especially important for us to eat vegetables like carrots and sweet potatoes.  Besides, we need to protect our eyes when we spend a long time in bright sunlight. The best way to do. this is by wearing sunglasses that have 100% UV (紫外线)  protection. What's more, it is necessary to protect our eyes when we work with dangerous chemicals (化学物质).  For this reason we should always wear goggles in chemistry labs at work or at school. Finally, we should not spend too much time in front of the computer or television screen. That is why doctors advise if we have to use a computer for a long time, we should take a short break every fifteen or thirty minutes.
Maintaining good eyesight is important. If we do these few simple things we can protect our eyes and reduce the chances of losing our eyes. As the popular English expression goes, “It's all fun and game, until someone loses an eye.” When people say this, they mean that losing an eye is a very terrible thing.
【小题1】When should we wear goggles?

—Where were you both at this time last night?

—Tom was writing an e-mail        I was watching TV at home.

A．as soon as         B．after             C．until             D．while

We have no idea about  1 men first began to use salt. But we do know that it had been used in many different ways    2  the history.

For example, in many history books it is  3   that people who lived three thousand years ago 4 salted fish. Thousands of years ago in Egypt（埃及）, salt 5  keep the dead. It can keep the dead bodies  6 decay.（腐烂）

In the eighteenth century, a person who stole salt was   7  to have broken the   8 . if a person was caught stealing salt, he would be thrown into   9  . Books also record that in England about ten thousand people were put into prison during that century   10  stealing salt! In the year 1553, if a man took   11  than his share of salt, he would be thought to have broken the law and would be   12  punished(惩罚).

Salt was very  13  on the dinner table of a king. It was always put   14 the king when he sat down to eat. Then important visitors sat near the salt   15 less important visitors were given seats farther away from it.

1.                A．when          B．where          C．what D．which

2.                A．throughout      B．thought         C．though   D．although

3.                A．say            B．reported        C．recorded D．reading

4.                A．eat            B．ate            C．eating    D．have eaten

5.                A．used to         B．was used to      C．was used  D．used

6.                A．off            B．from           C．on   D．out

7.                A．think           B．consider        C．thoughtful D．thought

8.                A．law            B．glass           C．computer D．time

9.                A．pool           B．hill            C．prison    D．river

10.               A．because        B．because of      C．by   D．as

11.               A．more          B．less            C．fewer D．most

12.A. serious    B. bad       C. terrible         D seriously

13.               A．important       B．necessary       C．clever D．cheerful

14.A. in the front of B behind  C. in front of     D. before

15.               A．when          B．as             C．however  D．while