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问题 单项选择题

从事视屏作业的人员，最易引起( )过度疲劳。

A．运动系统
B．视觉系统
C．消化系统
D．呼吸系统

答案

参考答案：B

解析： 从事视屏作业的人员，最易引起视觉系统过度疲劳。

选择题

已知⊙O1半径为3cm，⊙O2的半径为7cm， 若⊙O1和⊙O2的公共点不超过1 个，则两圆的圆心距不可能为[ ]

A.0cm

B.4cm

C.8cm

D.12cm

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填空题

用所给单词的正确形式填空。

1. Jenny ___________ (run) with a kite on the playground now.        

2. I brush my ___________(tooth) in the morning and in the evening.  

3. The weather is cold and ___________ (cloud).                      

4. His aunt ___________ (make) dumplings now.                        

5. His brother___________ (drive) to work every day.                 

6. It's 9:00 now. The children are ___________ (have) an English class.

7. He lives near school. He ___________ (walk) to school.             

8. February  is the ___________(two) month in a year.                

9. How many ___________ (season) are there in a year?                

10. He often ___________ (watch) TV on Fridays.                        

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