题干

某品牌滚筒洗衣机的电路图如图所示,筒门处有开关S1,筒门关闭时S1闭合,筒门打开时S1断开。筒门开关S1和控制开关S2必须同时闭合时,洗衣机才能工作。下列符合要求的电路模型是(     )

A:

B:     

C:

D:

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A

同类题2

完形填空

The Change of Bossy (好指挥人的) Lily

    I am a helpful person. However, my classmates used to call me “Bossy Lily”.

    One day, the class shouted again, “Bossy Lily, bossy Lily!” My teacher, Ms. Flora sent me to sit in the 1 for a while to quiet the class. I didn't understand why the class got 2 when I tried to show Mike how to handle the record player. I was only trying to 3 I also couldn't understand why the teacher had sent me to the corner. I was taught to always help my 4if they didn't know something. I thought the class was 5 in their judgment of me. I thought the teacher was wrong in 6 with them.

    When everyone was excused for break, Ms. Flora kept me in. I 7 I was in serious trouble, but I still didn't understand how my 8 could have caused the teacher to react like this.

     “Why am I here and not at break?” I asked Ms. Flora. The teacher didn't say a word.9 she placed a word puzzle in front of me. Surprised as I was, I got out my pencil and 10 to solve it. It was 11 with many words I didn't understand. I raised my hand for help, but Ms. Flora 12 me. I 13 with the word puzzle until I was about to give up. But I was not a quitter, so I stayed with the challenge. Soon I had solved the problem 14my own. I was so proud I did the puzzle by myself that I raised my hand high to get Ms. Flora's 15. Ms. Flora picked up the finished puzzle and 16.

    “I'm glad that you learned this important 17 from me.” I was 18. She hadn't done anything. Now she was taking the credit for my hard work!

    “Now perhaps you have learned to let other students make discoveries 19. After all, that is the fun of 20.”

    In that moment, I decided that I would never do anything that would cause them to call me “Bossy Lily” ever again.