英语中什么情况下代词放中间

由卜脊动词+副词构成的词组,代词作宾语时要用宾格放在中间，如：add up,think over; turn on / off /扮戚 up / down ; get back ; write down ; clean up , cheer up 等厅弊陵这类动词短语后接接宾语时,有两种情况,1.宾语是名词时,这个名词可以放在短语后,也可以放在短语中间；2.宾语是代词时,这个代词可就只能放在短语中间.如：
The radio is too loud . Please turn it down .
The teachers told the kids how to add up numbers.
The teachers told the kids how to add numbers up.
The teacher wrote some numbers on the blackboard and asked the kids to add them up.
They will think over the problem before they make the decision..
The problem is vital,and they are thinking it over.

一般来讲，由动词+副词所构成的短语动词伏空，如代词it/them作它的宾语时，岩厅宽要把it/them放在其中间;由动词+介词所构成的动词短语，如it/them作粗亮它宾语时，要将其放在后面。
1.由动词+副词
put down/on/off/in...
take out/up/down/off...
get on/off/down/....
hold back/down...
look up....
2.由动词+介词
look after/over/for...
take on/after....
get over/into...
put into...

一般来讲，由动词+副词所构成的短语动词，悔姿察如代词it/them作它的宾语时，要把it/them放在其中间;由动词+介词所构成的动词短语，如it/them作它宾语时，要将其放在后面。
1.由动词+副词
put down/on/off/in...
take out/up/down/off...
get on/off/down/....
hold back/down...
look up....
2.由动词+介词
look after/over/for...
take on/after....
get over/into...
put into...

动词+介词时 放后面

动词+副词时 代词放中间

及物动词时，可放中间；碧茄

不及册态物动词，不能放中间。

及物动词时，可放中间；
不及物动词，不能放中间。

动词+介词时 放后面

动词+副词时 代词放中间