The police have been observing his movements these days为什么observing不是observed

The police __________ out to look for the missing boy.A.has been B.be C.have been D.is The police have been observing his movements these days为什么observing不是observed the police ()to find the truth of the murder A.has being trying B.has been tried C.have been triedD.have been trying Having been 是什么时态Having been lost in the mountains for a week ,the two students were finally saved by the local police.为什么不是 have been lost 请帮忙分析一下这句句子的结构Have any clues been found that can help the police find the thief?Have any clues that can help the police find the thief been found 这样写可不可以? the police（）（drive）mad by the loud noise many times填have been driven还是will be driven? the police are investigating the company ,threef managers have already been arrestedA.whose B.that C.which D.where have been lost in the mountains for a week 为什么加been?have been lost in the mountains for a week ,the two students were finally saved by the local police.为什么加been?迷路不是主动迷路的吗? The police checked out his claims and found that he did have been wanted.意思“did have been wanted”什么意思 变间接引语My bicycle has been stolen,he said,I shall have to telephone the police. Oh dear!have you called the police? i won t be able to attend the lecture because___ i a report in my police thenA.will have writtenB.was writingC.have been writingD.will be writing believing these people have their special___,the police have been keeping a watch on them.A.ideas,good B attempts,close C ways,tight D minds serious I was on the highway when this car went past fllowed by a police car .They_____ at least 150 kilometers an hours.A.should have been going B.must have been goingC.could have gone D.would have gone to have been done结构怎么用Many of the crimes have gone ___,because some people dare not report them to the police.A to have been unnoticedB unnoticed帮我分析A错在哪里 Have any clues been found that can help the police find the thief是定语从句还是宾语从句是被动句吗 Police are now searching for a woman who is reported to (having been missing)since the flood hit the are last friday. 为什么是HAVING不是HAVE The local police have been chased the murderer for half a month这里为什么用have been警察是被追捕?还有,那个chase,是用过去式,还是用chasing?