The factory ----- Mr Li used to work was closed last week.填where 还是which ..

题目

The factory ----- Mr Li used to work was closed last week.填where 还是which ..
理由

答案

where
因为这里的先行词并不是从句中的宾语或者主语,所以这里要用关系副词where
我再举个例子：
The factory which Mr Li used to work in was closed last week.
这种情况下,先行词是从句中的介词的宾语,所以要用which