posted by rfvv .
1. My hobby is computer games.
2. My hobbies are computer games.
3. My hobby is a computer game.
4. My hobby is computer game.
5. My hobby is playing computer games.
(#5 is right. What about the others? Which ones are grammatical?...thank you for your answer.)
1, 2, and 5 are correct as they are.
4 is incorrect.
3 is correct if you mean one particular computer game.
Again, though, including the word "playing" makes the sentence make best sense.