in return和in return for的区别详解：
in return for sth. 作为…的回报/交换
in return 作为回报/交换

1.in return单独用，不后接内容
I will help you, but I want something in return.
我会帮你，但是我要回报。
She helps me and expects nothing in return.
她帮助我，并不期望有回报。
He told me his secret. In return, I told him mine.
他告诉我他的秘密。作为交换，我告诉了他我的秘密。

2.in return for sth.
I looked after her baby in return for a free meal.
我照顾她的宝宝，以免费餐作为交换。
Lily did the housework in return for a new toy.
莉莉做家务，以新的玩具作为回报。