i don't know how old you are在什么情况下,像这样的名词性从句,后面的跟着的疑问句的主谓要倒装?为什么有些要,有些却不要,有点乱,

i don't know how old you are其中how old you are是倒装吗? How old is he? I don't know （变为同义句）I don't know ____ ____ i don't know how old she is ,but she_____ be over 40 I don't know how old he is 同义句转换 I don't know.How old are you?改为同义句 I don't know.How old are you?合并为一句 I don't know how old he is.(改为同义句） I have__ __how old he is. 【合并英语句子】.I don't know.HOW old are you?合成I don'tknow_ _ _ _. 合并英语句子.I don't know.HOW old are you?合成I don'tknow_ _ _ _.. I don't know how to i don't know how to I don't know .how old are you?(合并为一句）I don't know —— —— —— —— how to play basketball?I don't know.who know? 情问：I don't know --------怎么填?（A.he is how old B.is he how old C.how old is he D.how old he is)能说一下相应的语法知识,并举一个例子吗? i don't know how to do it句型转换i don't know[ ][ ][ ]do. i don't know how与 i don't know why有什么区别? i don't know how i feel的中文 I don't know how can I ask questions?