1. That's right.
2. That's spot on.
3. You've hit the nail on the head. / You've nailed it.
4. I suppose so. (use this when you agree, but you are not completely convinced)
5. I'm afraid you're right. (use this in response to bad news, to say the bad news is correct)

Animal Facts
When a viper fish wants to eat a large meal, it moves all its internal organs towards its tail to make more room inside it for food.      .. More >>