成语动词有两种情况：
1.不及物动词 + 介词,如：
look after 照顾,关心
look for 寻找
pay for 偿还,赔偿
这类动词由于是由动词和介词构成的,所以要求宾语必须跟在介词后面,无论该宾语是名词还是代词,比如：
I must stay at home to look after my mother.(宾语 my mother 是名词)
My mother is ill and I must stay at home to look after her.(宾语 her 是人称代词)
2.及物动词 + 小品副词,如：
put on 穿上,附上
take off 脱去,拿开
pick up 检起,搭乘
这一类成语动词中的动词本身就是及物的,因此如果宾语是名词,既宾语可以放在动词和副词之间,也可以放在副词后；但是当宾语是人称代词时,宾语要求只能放在动词和副词的中间.举例如下：
Please put your coat on.请把外衣穿上.(宾语 your coat 是名词)
Please put on your coat .请穿上外衣.(宾语 your coat 是名词)
Here is your coat.Please put it you.给你的外衣,请把它穿上.(宾语 you 是人称代词)
I'll pick you up in the car this evening.(宾语 you 是人称代词)
I'll pick my neighbour up in the car this evening.或 I'll pick up my neighbour in the car this evening.（my neighbour 是名词 ）
但是说成 I'll pick up you in the car this evening 是绝对不行的.
