把下列英文谚语翻译成中文
1.A faithful friend is hard to find.
2.Each bird loves to hear himself sing.
3.Early to bed and early to rise makes a man healthy , wealthy and wise.
4.Eat to live , but not live to eat.
5.It is easier to get money than to keep it.
6.It is easy to open shop but hard to keep it.
7.It is hard to please all.
8.It is never too old to learn.
9.Not to advance is to go back.
10.To know everything is to know nothing.
11.To know oneself is true progress.
12.To save time is to lengthen life.