试题与答案

黑白显像管的第二、四阳极与()组成电子透镜,使电子束在轰击荧光屏之前聚焦。A、控制栅

题型:单项选择题

题目:

黑白显像管的第二、四阳极与()组成电子透镜,使电子束在轰击荧光屏之前聚焦。

A、控制栅极

B、加速极

C、阴极

D、聚焦极

答案:

参考答案:D

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题型:阅读理解

读一读,根据对话判断正(√)误(×)。

Sarah: Excuse me. Where is the cinema?

John: It's east of the post office.

Sarah: How can I get there?

John: Turn left at the traffic lights, then go straight. It's on your right.

Sarah: Thank you.

John: You're welcome.

( ) 1. Sarah wants to go to the cinema.

( ) 2. The cinema is at the traffic lights.

( ) 3. Sarah turns right at the traffic lights.

( ) 4. The cinema is east of the park.

( ) 5. Sarah gets there on foot.

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