1. I like pears, too.

Question

2. I like pears too.
3. I like pears, as well.
4. I like pears as well.
5. I don't like pears, either.
6. I don't like pears either.
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1,2,5,and 6 are grammatical, aren't they? How about #3? There is a comma before 'as well.' Is this expression correct?

Answer 1

1, 3, 5 - correct.

4 can be considered correct, too, depending on the meaning.