I was reading a novel and in the novel I read a sentence, which did not sound fine to me.
From the novel:
He always escaped to go study.
But I knew it was perfectly (as I trust the writer and I am a non-native English speaker) fine there, but I need to know where and when should I avoid to before some words (maybe they are adverbs)? I also know that we do not use to before them (as they are adverbs):
Home, out, outside, somewhere, anywhere, nowhere, abroad, downtown, downstairs, upstairs, underground, there, here, in, inside.
We do not use to before them as well (I think study comes in this category):
go play, going shopping, go shopping.
My question is that are they also adverbs? if yes then please let me know the list when I should avoid to before them.