all things are difficult before they are easy.
all work and no play makes jack a dull boy.
只会用功不玩耍，聪明孩子也变傻。
a man becomes learned by asking questions.
不耻下问才能有学问。
a man can do no more than he can.
凡事都应量力而行。
a man cannot spin and reel at the same time.
一心不能二用。
a man is known by his friends.
什么人交什么朋友
