1.Tom has__experienced a lot of natural disasters, such as hurricanes, thunderstorms and tornadoes, so he says he himself is a man with unforgettable experiences and has got a lot of experience;__that is, he is experienced in dealing with natural disasters.(experience)
2.①Alcohol is the most common cause of traffic accident.
②What caused him to__change(change) his mind at last？
③The big fire is finally brought under control, but extensive damage has__been__caused(cause).
④I hope the children haven’t__caused__you__too__much__trouble(给你添麻烦).
3.①(2019·山西康杰中学高一期中)Jimmy was working in the lab when the power cut occurred(occur).
②It occurred to me to__visit(visit) my close friend when I was in Beijing last week.
③It occurs to me that we could paint the walls a lighter colour to make the room look bigger.
④A__good__idea__occurred__to__me(我想到一个好主意) this morning when I was brushing my teeth.
