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问题 单项选择题

甲型肝炎病毒有（）

A.1个血清型

B.2个血清型

C.3个血清型

D.4个血清型

E.5个血清型

答案

参考答案：A

解析：属于理解、记忆题。考学生对HAV病原学和血清学的认识。预测错误率不高。常见错误：选答"B"，学生多误以为有两个血清型。

阅读理解

阅读理解。

      American school life is different(和…不同)from Chinese. American students usually get to school at around 8:30 in the morning. School starts at 9:00. They put their school bags in their lockers(柜子)and only take one book, one notebook and one pen to each class. In class, American students can sit in their seats(座位)when they answer their teachers’ questions. They often ask lots of questions in class.

      At around 12:00 students have lunch. American students don’t go home for lunch. They have it at school. Most students like chicken, hot dogs or hamburgers. At 13:00 in the afternoon, they begin to have classes. Their classes are usually over at 15:00. Then they join in school clubs or play sports.

1. American School starts at ______ in the morning.

A. eight thirty            

B. nine o’clock    

C. nine thirty

2. American students usually ______ in class.

A. eat lots of chicken      

B. read lots of books      

C. ask lots of questions

3. American students often ______ at 15:30 on weekdays(工作日).

A. play sports      

B. have classes      

C. eat lunch

4. The best title(标题)of this passage is “______”.

A. American School Clubs

B. American School Life

C. American School Dinner
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选择题

氯化钙溶液中含有少量盐酸，欲中和盐酸使溶液呈中性，在没有指示剂的条件下可选用的试剂是（　　）

A．熟石灰

B．生石灰

C．石灰石

D．纯碱
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