精选优质文档-倾情为你奉上 第五单元复习题1. Earthquakes(地震)always happen _, so it is difficult to know when they come. A.usually B.suddenly C.luckily 2. Jack called his mother at 7:30 yesterday, but she didnt pick up at that time. A.answer B.speak C.talk D.ring 3. Please check(检查)your paper to _there are no mistakes. (错误) A.think of B.try out C.find out D.make sure 4. My mother _