Question

1. I don't play computer games much.
2. I don't play computer games a lot.
3. I don't play computer games more than my brother.
4. I don't play computer games as much as my brother.
5. I don't play computer games less than my brother.
6. I play computer games more than my brother.
7. I play computer games as little as my brother.
8. I don't play computer games as little as my brother.
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Q1: Would you check the sentences?
Are they all grammatical?
Q2: Which one is right, #1 or #2? Are both OK?

Answer 1

#s 1 and 2 are fine as they are.

I'd use these replacements:

3. I don't play computer games more than my brother does.

4. I don't play computer games as much as my brother does.

5. I play computer games as much as my brother does.

6. I play computer games more than my brother does.

7. I play computer games less often than my brother does.

8. (See #3.)

If you don't have "does" at the ends of those sentences, then it's not clear if you mean playing computer games or playing your brother!