perhaps的使用方法

No one, save perhaps his wife, knows where he is.

这句话中，perhaps本身为副词，就顺序而言，perhaps坐落于介词save和其宾语his wife之间，这种表达相对于perhaps放最后（save his wife perhaps ）哪一个比较好？还是没不同？

perhaps 一般放在句首，也可以放在 be 动词后面，但不可以放在句末。