题干

小明对卫生间内的换气扇和照明灯的电路进行了如下改造;控制它们工作的有两个开关,换气扇工作时照明灯一定发光,照明灯发光时换气扇可以不工作.如图的虚线框内已画出了所连接的电源,请你接着完成这部分电路的电路图(换气扇用电动机符号表示).

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Jack had an unusual experience last night. He is sharing it with his friends. Ken and May.

Ken: What were you doing, Jack What did you see

Jack: It was half past nine last night and I was getting ready for bed. I heard some strange noise outside while I was brushing my teeth. I wondered what was happening and I went to the window and looked out. To my surprise, I saw a bright yellow green light in the sky.

May: Maybe the light you saw was a UFO! Or a ghost! A few years ago, an American man saw a flying saucer while he was driving along a road. He also saw some strange yellow light. You have heard about it, haven't you

Ken: Don't be imaginative, May. Jack didn't see anything, or anybody. It wasn't a ghost. It was probably a plane, or a shooting star .Perhaps Jack just made a horrible dream!

Jack: I am very serious .I did see something. The light disappeared and then suddenly some “tiny people” were standing in the garden .There were four of them .Two of them ate some flowers in the garden .It was always stretching out its arms.

Ken: Oh, come on, Jack. I really doubt what you have said.

Jack: I am not joking! One of the people was looking at me through the window.

May: Really What did it look like Were you frightened

Jack: Its whole body was green. It had no ears and nose. Its hands were huge. Its eyes were very big and resembled eggs. It started at me and I could hardly move.

Ken: What happened then ?

Jack: I was able to move eventually. I ran and got my camera immediately.

May: And......

Jack: I didn't have a film.

May: Oh no!