A question about English

问题描述:

A question about English
Many guide dogs that have worked for years know all of places their master usually goes.
为什么句末不用加to,不是go to the places吗?

又一个有点钻牛角的小朋友~
你尝试把句子补充完整
Many guide dogs that have worked for years know all of places (where) their master usually goes.
看出来了吗?go where
where 是副词,就和home一样,因此不加 to