为什么可以省略IS?Do you think it necessary to...是不是少了个is?那I don’t think it is necessary to leave so early.是对还是错？

The only thing that I can do is give you some money.为什么可以省略to?这是formal Do you think it (is) advisable that college students fall in love?这句话为什么可以省略掉is,系动词以可以随便省略吗?还有后面为什么要用原型fall in love? 谢谢喽! Do you know the girl who just came in?的who可以省略吗?为什么? Do you know what we are working for?为什么for不可以省略? 为什么可以省略IS?Do you think it necessary to...是不是少了个is?那I don’t think it is necessary to leave so early.是对还是错？ There is something you should know为什么连接词可以省略,There is something which you should know man who helped you is Mr White.”帮手指出句子中的主语,谓语,还有who可以省略吗?为什么.那who在什么情况下可以省略. i will do what we can to help you这句话中what we can( do)后面这个do 为什么可以省略呢 he is the man (whom/that/who) you just talked to为什么那三个可以用,还可以省略? i can do whatever you want me to do 可以省略do吗 It is no wonder you were late.这句中为什么后面的主语从句省略了that?主语从句不是不可以省略that吗? 是how much do you think it is?还是how much do you think is it?此处的do you think是什么成分?可不是how much do you think it is?还是how much do you think is it?为什么?此处的do you think是什么成分?可不可以省略? ----____ should get the job,peter or sandy?---I think Sandy should get the job.A.Who do you thi----____ should get the job,peter or sandy?---I think Sandy should get the job.A.Who do you think B:Do you think who 选B不可以吗？为什么？ people make a promise will do whatever they can (do).为什么可以省略do. all she does is cry←省略了to?为什么可以省略? There is something you should know这句话有问题没,是不是定语后置,为什么不是 There is something which is you should know为什么连接词可以省略，谢谢，There is something which you should know 请问,you can do what you want to do中,结尾的do可以省略吗?即you can do what you want to,这句话正确吗? Do you have tea by youself可不可以改称用 have提问 比如 Have you tea by youself为什么那么Have you finished alrely,怎么 可以Have you been to there before,have been to 固定短语怎么可以省略吗