问题 单项选择题

以下说法错误的是()

A.甲型肝炎的发病有周期性起伏现象

B.人群无论年龄大小对HBV普遍易感

C.HBsAg携带者不能献血以及从事保育工作

D.乙型肝炎和丙型肝炎都有家庭聚集现象

E.对易感者接种丁肝疫苗,乙型肝炎的感染也会随之减少

答案

参考答案:E

解析:E的说法错误,因为通过对丁肝易感者接种乙肝疫苗来消除HDV感染所必须的条件。现在丁肝疫苗还在研制中。

阅读理解

根据短文内容,完成下面各题。

    The Internet has become an important part of teenage life. Most of them use the Internet to get lots of

knowledges and information, and to relax in their spare time. The teenagers keep in touch w  1   their friends

online. It is cheaper than phoning someone far away and e-mail is also much q  2   than ordinary mail. 

    But some teenagers are not using it in a good way. Many would find life difficult without it. Many teenagers

spend too much time online. Some of the students who used to do w  3   at school are now failing in exams

because now they spend all their time p  4   games online.

    It is important that you use the Internet in a proper manner. Teenagers should learn h  5   to use the Internet

for study and keep away from bad websites.

    Teenagers should make sure that surfing the Net doesn't take the place of their homework or being with

their friends.

A. 根据短文内容及首字母提示,写出所缺单词。 

    1. ________ 2. ________ 3. ________ 4. ________ 5. ________

B. 根据短文内容,判断正(T)误(F)。

    ( )6. Most teenagers use the Internet to get lots of knowledges and information.

    ( )7. The teenagers don't like keep in touch with their friends online.

    (     )8. All the teenagers are using the Internet in a good way.

    (     )9. Some of the students spend too much time online.

    (     )10. Teenagers should make sure that the Internet can't take the place of everything.

选择题