#1 is correct.
#s 2 and 3 are not.
1. I haven't read Harry Potter yet.
2. I don't read Harry Potter yet.
3. I didn't read Harry Potter yet.
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Which expressions are not grammatical?
Is #2 or #3 grammatical?
3 answers
PS -- #3 could be correct if "yet" were removed.
#1 is right