问题
判断题
纯净的半导体中，自由电子和空穴数目有限，因而导电能力差。但如果在其中掺以杂质，则导电能力会大大提高
答案
参考答案：对
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纯净的半导体中，自由电子和空穴数目有限，因而导电能力差。但如果在其中掺以杂质，则导电能力会大大提高
参考答案：对
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| The future belongs to those who believe in the beauty of their dreams. -Eleanor Roosevelt My home is a place of great beauty and agricultural richness, as well as of war and natural disasters. When I was only fourteen years old,I was filled with 1 in spite of the terrible surroundings.The families living here,who tried to make their living fromthe land, 2 great losses. I felt sorry especially for the 3 , but I 4 to be hopeless.I decided that where I was,I could do 5 to help them. I began knocking on every door and saying to each person who 6 my knock,"I know that you are 7 and give the birds that come to your yard a little 8 . Please consider me your bird. Give me only a handful of rice each week when I come to your 9 . I will take it to the temple where it can be given to the 10 children. " No one seemed to 11 giving me a handful of rice, even 12 they had little themselves. On Sunday, I would go to the 13 and give my handfuls of rice to the monks to 14 to the children. One day,I came to a house that had 15 to give.I told my story and asked if I could be their bird. The woman called her daughters, and 16 gave me fifty cents,as well as the handful of rice! I began to ask for 17 and rice from the other "bird feeders" ,and they gave them to me. Everyone was happy to be helping those who were suffering,even 18 only this small way. The temple was soon able to help everyone who came to them for food and clothing. "Consider me your bird. " My 19 idea had not stopped the war,but anyway, it was 20 some peace. | ||||
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