1 Never trouble trouble till trouble troubles you.

2 I think that that that that that student wrote on the blackboard was wrong.

3 I know. You know. I know that you know. I know that you know that I know.

4 We must hang together, or we'll be hanged separately.

5 The quick brown fox jumps over a lazy dog.

6 Was it a bar or a bat I saw?

7 To China for china, China with china, dinner on china.

8 2B or not 2B, that is a?

9 He never saw a saw saw a saw.