What is the classic sentence of pun?

1, breaking pipes (harmonic Tong Guan's) and sprinkling grain (harmonic Cai Jing's) are good times on earth.

2, the big test quiz, burning me (test).

3, break the salt (reconcile Yan Xishan's surname) and smash the sauce (reconcile Chiang Kai-shek's surname), and the people will have a good life.

When you go to the toilet, don't forget to come and go in a hurry.

5, don't just copy, think hard, so as not to become a printing (copying) machine.