激光打印机的激光机头由激光光源、旋转反射镜、聚焦透镜和感光鼓等部分组成。其中______ 表面涂有光电转换材料，计算机输出的文字或图形以不同密度的电荷分布记录在它表面，以静电形式形成了“潜像”，然后再以电子照相的方式在纸上输出。
参考答案：感光鼓
解析：
[分析]： 感光鼓表面涂有光电转换材料，计算机输出的文字或图形以不同密度的电荷分布记录在它表面，以静电形式形成了“潜像”，然后再以电子照相的方式在纸上输出。
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| Liu Bing is Zhang Kun's friend, and now he is in a high school in Ottawa. This is a letter __1__ Liu Bing to Zhang Kun. Dear Zhang Kun, Thank you __2__ your postcard. I'm __3__ to you in the reading room. Now I have many new friends here. Henry is one of them. He is my classmate. He is 14 __4__ old. His mother is a Canadian, but his father is from Australia. He often __5__ me to go to his home for dinner __6__ his parents. His family like China very much. At school, we have many good teachers. One of them is from the USA. We __7__ her Miss Green. She teaches English. Our French teacher is Mr. Smith, and he is from Paris. He loves __8__ very much, and we all love him. Our Chinese teacher is Mr. Scott, and he likes Chinese kung fu very much. After school, he often talks to me in Chinese. __9__ is your English now? I want to know something __10__ you very much, please write to me soon. Yours, Liu Bing | |||
| ( ) 1. A. for ( ) 2. A. for ( ) 3. A. telling ( ) 4. A. year ( ) 5. A. tells ( ) 6. A. and ( ) 7. A. calls ( ) 8. A. us ( ) 9. A. What ( ) 10. A. about | B. to B. with B. talking B. month B. asks B. with B. tell B. we B. How B. at | C. from C. at C. writing C. months C. ask C. for C. tells C. I C. Where C. in | D. at D. to D. speaking D. years D. call D. in D. call D. it D. Who D. for |