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问题 单项选择题 A1型题

远中孤立磨牙上的圆形卡环的非倒凹对抗臂上设计并行双臂作用（）。

A.提高卡环的强度

B.增加卡环的弹性

C.恢复咬合接触

D.间接固位作用

E.防止食物嵌塞

答案

参考答案：D

选择题

甲、乙、丙三个同样的瓶子分别装着质量相等的水、煤油、汽油（ρ汽油<ρ煤油<ρ水）。甲瓶液面最高，乙瓶次之，丙瓶最低。则（  ）

A．甲瓶装着汽油，乙瓶装着水

B．甲瓶装着水，乙瓶装着煤油

C．甲瓶装着水，乙瓶装着汽油

D．甲瓶装着汽油，乙瓶装着煤油
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写作题

下面是学校为保护学生视力做出的要求。请根据以下要点写一封信告诉你的朋友Jack怎样保护视力。要点：1. Hold a book at least 30 cm away from the students’ eyes while reading.

2. Place the computer at least 50 cm from the students.

3. Look out of the window at objects that are far away.

4. Check the students’ eyes regularly by a doctor.

5. Do eye exercises both at school and at home.

要求: 可适当增加细节。词数100字左右。

Dear Jack,

How are you getting on with your studies? I’m sorry that you have got the eyesight problems. ____________________________________________________________________________________________________________________________________________________________________

Yours truly
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