I will never forget these days (which )we spent together.为什么填which,而不是when,

问题描述:

I will never forget these days (which )we spent together.为什么填which,而不是when,

先行词these days 在从句中作宾语,所以只能用关系代词which ;如果先行词在句中做时间状语的话,则要用关系副词when.
例如:I still remember the day when I first came to Beijing.