为什么是work on it而不是work it on?也有cup them up啊!这些怎么区分?

为什么是work on it而不是work it on?也有cup them up啊!这些怎么区分? 为什么是work on it而不是work it on?也有cup them up啊!这些怎么区分? work on的代词The matter was serious,so the manager decided to work on it immediately as soon as he reached the office.为什么是“work on it”而不是“work it on”呢?不是代词要放中间吗?这个我在网上搜不到。 为什么是it’s down Center Streen on the right 而不是It’s on Center Street on the right I found it easy (to work) out the problem in this way. 括号内为什么是to work?而不是work的其它形式谢谢啦. How long does it take you go to work by bike every day? 为什么是用take而不是用spend 为什么是on fifth avenue而不是on the fifth avenue 句首 为什么是come on 而不是coming on It is necessary that an efficient student ___his assignment on time.答案为什么是complete 而不是completes? What 's that on the grass?---It's -----sheep为什么是a litter 而不是a few,不可数吗 为什么是It is said that 而不是It said that 为什么是take it home 而不是take it to home? 为什么是look for it 而不是Look it for 为什么是take it home 而不是take it to home? 英语-为什么是it was he而不是it was him 为什么是picked it up,而不是picked up it 为什么是mix it up而不是mix up it? 为什么是I work with people and money而不是My work呢?