Bad times make a good man. 艰难困苦出能人。 There is no royal road to learning. 求知无坦途。 Doubt is the key to knowledge. 怀疑是知识的钥匙。 Sharp tools make good work. 工欲善其事,必先利其器。 Wasting time is robbing oneself. 浪费时间就是掠夺自己。
