Using "no" as a negative:
* "I have no idea where the keys are."
* "No, thank you, I'm not hungry."
* "There's no way I can finish this project by tomorrow."
Using "know" to express knowledge:
* "I know the answer to that question."
* "Do you know how to get to the library?"
* "I've known her for years."
Using both words in a sentence:
* "I know you're tired, but we have to go."
* "No, I don't know what you're talking about."
* "I know that you're trying to help, but I don't need your help."