B．people who don't care about themselves

C．people who are very sexy

D．people who often have sex

答案　A

2．We can infer from the passage that .

A．HIV is equal to AIDS

B．HIV is different from AIDS

C．HIV weakens a person's immune system

D．people can have HIV in their blood for quite a long time

答案　B

3．In order to stay safe，you .

A．should not share needles with someone else

B．have to avoid using anything else that the person has used while injecting drugs

C．should use a condom if you have sex with another one

D．all of the above

答案　D

重点词汇

He felt he had to make up his mind on every step instead of taking risks.

他觉得他不得不每一步都要下定决心，而不能冒险。

(take risks/a risk冒险

※at the risk of doing...冒着......的风险

at risk处境危险；遭受危险

※risk (doing) sth.冒险(做)......；冒着......的风险

(1)A rescue worker risked his life saving two tourists who had been trapped in the mountains for two days.(2018·北京)

一位救援人员冒着生命危险救了两名被困在山里两天的游客。

(2)Your health might be at risk due to much smoking.由于吸烟过多，你的健康可能受到威胁。

(3)He jumped into the river at the risk of losing his life.他冒着生命危险跳进了河里。

(4)We don't want to risk being caught(catch) in the traffic jam.我们不想冒堵车的风险。