A：过去木匠用锯和刨来加工木头，木头不动工具动，人们从工具不动木头动的角度出发，设计发明发电刨。
B：奥斯特发现电可以转变为磁，法拉第从中受到启发，将磁又转变为电，为发电机的发明奠定了基础。
C：人们把原有煎鱼锅的热源由锅的下面安装到锅的上面，设计出了无烟煎鱼锅。
D：一些人提出要研制发明一种不需要提供动力或能源而能够永远不停地转动的永动机。
阅读理解 Betty is an American school girl. She is very happy because her parents will take her to China for a visit. They are going to fly from New York on June 30 and get to Beijing on July 1. They will stay at Lido Holiday Inn. Their Chinese friends will show them around Beijing. They are going to visit the Palace Museum, the Summer Palace, the Temple of Heaven and the Great Wall. They will also visit some Chinese homes and try some Chinese food. They will spend a week in Beijing and then go to Xi’an, Guilin and some other places for sightseeing. The whole trip will take three weeks and she is sure she will have a great time in China.
判断对错
从圆内到圆上任意一点的线段叫做半径．
某人因为交通事故脊髓从胸部折断了，一般情况下( )
