1. He used the phrase you know so often that I finally said, No, I don‘t know.

2. He used the phrase "you know" so often that I finally said, No, I don‘t know.

3. He used the phrase you know so often that I finally said, "No, I don‘t know."

4. He used the phrase "you know" so often that I finally said, "No, I don‘t know."

5. He used the phrase "you know" so often that I finally said "No I don‘t know."