是不是in return？意思：作为回报He gives me an apple,in return,I give him one.他给了我一个苹果，作为回报，我给了他一个。或者加一个for : in return forIn return for his apple,I give him one.为了回报他给我的苹果（谢谢他给我苹果）我给了他一个。
in turnadv.依次, 轮流n.依次,而,又
