I paid a lot of money for this ring and___I lost it on the train!

题目

I paid a lot of money for this ring and___I lost it on the train!
这里答案是Yet.Yet和however都有表示然而,转折的意思,为什么这里不能用however呢?

答案

however应该用逗号隔开如：
I paid a lot of money for this ring and however,I lost it on the train!