what is it that is not an airplane but moves through the sky,not a river but is full of water?

what is that?It is C.为什么是 It is? What is this?It is ----------N what is it that i want? That's just what it is here. 为什么what is that要用 it回答 that's what it is翻译下 that's what it is 歌词 What's that?Is it banana,tow? what is it that is always coming but never arrives? What is that _______Chinese,Jim? It is 黑板 what is that?IT IS A ORANGE?哪错了 and what is that in your( )( is it a pen? What is that? It is a cat 有语法错误吗 对that is just what it is here如何提问 What is that in English?--It is computer.改错句 What is the difference between “What is that and What is this?Translate it into Mandarin what is this what is that 必须用it is 用this is ,that is 错误吗 为什么What is this?What is that?以及What is it?都只能用It is来回答.