能分一下句子的主语/谓语/宾语
You may have some idea of _what__the astronauts have to deal with if you try to drink a glass of water while standing on your head or while just lying down.
如果你试着倒立着或仅以躺着的姿势去喝水,就能大致体会到宇航员必须应付什么了.