Thanksgiving is a day when people take time to reflect on__ they are grateful for in their lives.

题目

Thanksgiving is a day when people take time to reflect on__ they are grateful for in their lives.
选项里有what who 答案选what 我不是很能理解 为什么不选who表达他们所感激的人呢?

答案

首先,这是what引导的带疑问词的宾语从句.例如：
I don't know who you are.我不知道你是谁
Noboby knows what he is thinking about.
没有人知道他在想什么
楼主,你的那句话是what引导的宾语从句做on的宾语
who 在语法上和what一样,也是可以的.
但感恩节要感谢的不只是人,还可以是上帝,大自然的恩赐.所以who只限于人,而what既可指人又可以指物
希望能够帮到楼主^_^