2. Definitely! 当然!

3. Certainly!当然。

4. It's for sure! 那是一定的。

5. Sure thing! 毫无疑问。

6. You bet! 当然。

7. You betcha! 那还用说。

8. No doubt! 无疑。

9.There's no doubt about it! 毫无疑问!

10. It's in the bag.十拿九稳。