He has three sons ,and all of them are docHe has three sons ,and all of them are doctors.这个句子中为什么of后用的是them而不是they?

定于从句问题① He has three sons, none of __A___ is a doctor. ② He has three sons, but none of ___B_ is a doctor. ③ He He has three sons .( )is a doctor.( )is a worker.( )is a teacher 怎样填 he has three sons,all of whom____(die)during the war== Mr Brown has three sons,two of them are doctors,______is a postman. He has three sons ,and all of them are docHe has three sons ,and all of them are doctors.这个句子中为什么of后用的是them而不是they? 英语翻译He has two sons,___is a doctor,____is a teacher He has two sons.One son is a doctor .The other son is a teacher 猜谜语：Two tathers and two sons went to a bookstone.They bought three books.Every has a book.Why Two fathers and two sons went to a bookstore.They bought three books.Every has a book.Why? once upon a time there lived an old man.He had three sons .One day ,he called them together and He has two sons, ( )of them lives with him. A .each B.neither C.either The mother has three sons._____of them are teachers.A.No B.Every C.All 请帮忙同时告知原因. 高中定语从句 The old man has three sons,all of ____ wew working abroad.A whom B who Mr.White has two sons ,and each of them has a sister.how many childen does he have? Alice has two sons.is Tim and is Tim.A.One,the other B.One,one C.He,he 不定代词一定要放从句句首吗?He has three sons.All of them are doctor.两个句子合成一个.He has three sons,____________________.是All of whom are doctor还是 Whom all of are doctor?改错：China has many islands，of them Taiwan i He has two sons ,one is a doctor ,the other is a teacher.one.the other .是固定搭配吗? the old man has two sons.one is a worker;_____ is a teacher.he old man has two sons.one is a worker;_____ is a teacher.a.another b.the other为什么不是A?那another 也是‘另一个’