题目

----Does she like playing ______ guitar?-----Yes. And she likesplaying _____ soccer,too.A． the; /B. /; / C. the; the. 答案：A弹奏乐器时要加the玩球时则不用故选A 据统计：有许多重大火灾都是因输电线老化，绝缘性能降低出现短路所造成的，教训十分深刻．请你用所学物理知识分析因电线短路而产生火灾的原因．