为什么claim to have done可以,而say to have done不可以?

为什么claim to have done可以,而say to have done不可以? Don’t claim to know what you don’t know.The job applicant claimed he had a college degree.The scientists claimed to have worked out a better solution to the problem.请翻译 issue a claim if it is the same problem,we will have to issue a claim for this material,这里issue a claim的意思是什么? if he were to claim insanity...为什么用were don.,t have to 动词不定式to have seen怎么替换?是将have换成be还是being,或者干脆换成that they have seen?整句是这样,They claim to have seen monsters in the sea.我需要解释怎么换,为什么. many ads claim that products have...这句话里的claim是做many ads claim that products have...这句话里的claim是做名词还是动词?为什么? we don't need to have too much fruit for .为什么用don't need to claim to have done sth 是声称做过某事 可是to do 和 to have done 有什么区别? they don't have places to live 还是 they don't have places to live in?为什么 you don't have to smoke in the non-smoking room.为什么用don't have to 英语翻译第一句是Fishermen and sailors sometimes claim to have seen monsters in the sea. I Don't Have To make a claim to 1.Does anyone make a claim to this book?make a claim to 是固定搭配吗?2.If you listen to me ,you (shall) get that cartoon book,my dear.为什么不用will you don't have to worry about it.为什么用have? you don't (have) to worry about it.为什么填have? claim用法带to do I really don't want to do that ,but I have to还是have to do?为什么?说清楚!