Ⅰ. hand in “传递、交给”。指交作业等。如：
The teacher told them to hand in their exercise-books. 老师要他们交作业本。
Ⅱ. turn in “上交、交出”。指将某物归公。或交给上级或组织以便找到失主。一般也可与hand in 互换。如：
① You should turn in the money. 你应该把那钱上缴。
② You should turn in / hand in your finished homework.你们应该把完成的作业交上来。