1. I like pears.

- Me, too.
- Me too.
- I like pears, too.

2. I don't like pears.
- Me, neither.
- Me neither.
- I don't like pears, either.
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Are the answers all grammatical? Do you have some more common answers?
Do we have to put commas after 'Me'? If both are possible, which expression is commonly used, 'with a comma' or 'without a comma'?

I recall being taught that the comma is used as in "me, too", but it often is not. I can find no "rule" about it. I think it may or may not be used in any of these examples at your option. Ms. Sue or Writeacher may know of a rule that I don't know of or is not in my grammar manual.

Yes, all the answers provided are grammatical and can be used to express agreement or disagreement with the statements.

There are some other common ways to respond as well:

1. Agreement:
- Same here.
- I feel the same way.
- That makes two of us.

2. Disagreement:
- Neither do I.
- I feel the same way.
- That makes two of us.

As for the use of commas after 'Me,' it is generally optional. Both with and without the comma are commonly used. It mainly depends on personal preference or style. However, if 'Me' is followed by a longer phrase or clause, using a comma helps to clarify the sentence structure. For example:
- Me, too, especially the ripe ones.
- Me neither, because I'm allergic to them.

In short, the use of a comma after 'Me' is not mandatory, but it can be used to add clarity to the sentence.