1.A close mouth catches no flies.
病从口入。

2.Knowledge makes humble, and ignorance makes proud.
博学使人谦逊，无知使人骄傲。

3.A man becomes learned by asking questions.
不耻下问才能有学问。

4.Whatever you do, do with all your might.
不管做什么，都要一心一意。

5.Better be out of the world than out of fashion.
不合潮流不如脱离尘世。

6.A bad workman always blames his tools.
不会撑船怪河弯。

7.He who does not advance loses ground. /Not to advance is to go back.
不进则退。

8.No cross, no crown.
不经风雨，怎能见彩虹。

9.Misfortunes tell us what fortune is.
不经灾祸不知福。

10.He that will not work shall not eat.
不劳动者不得食。

11.It never rains but it pours.
不鸣则已，一鸣惊人。

12.Better late than never.
不怕慢，单怕站。

13.Be slow to promise and quick to perform.
不轻诺，诺必果。

14.If you venture nothing, you will have nothing.
不入虎穴，焉得虎子。

15.A bad beginning makes a bad ending.
不善始者不善终。

16.Learn not and know not.
不学无术。

17.Don't try to teach your grandmother to suck eggs.
不要班门弄斧。

18.Don't put the cart before the horse.
不要本末倒置。

19.Don't claim to know what you don't know.
不要不懂装懂。

20.Don't have too many irons in the fire.
不要揽事过多。