1.Good medicine tastes bitter. 
良药苦口/忠言逆耳。

2.No pressure, no diamonds. 
天将与之，必先苦之。

3.Dream big and dare to fail. 
锐意进取，无惧挫折。

4.Passion begets persistence. 
唯有热爱，方能坚持。

5.Your only limit is your mind. 
唯思想是人类的局限。

6.Failure is the mother of success. 
失败乃成功之母。

7.Be positive. Be true. Be kind. 
积极。真挚。友善。

8.God helps those who help themselves. 
天道酬勤。

9.Every dark cloud has a silver lining. 
天无绝人之路。

10.Every minute/moment counts. 
争分夺秒/分秒必争。

11.Slow but steady wins the race. 
稳扎稳打/厚积薄发。

12.True happiness lies within you. 
真正的快乐发自内心。

13.Happiness depends upon ourselves. 
快乐源于内心。

14.What you believe, you can achieve. 
有志者，事竟成。

15.A sure friend is known in unsure times. 
患难见真情。

16.Suffering is needed to succeed. 
要成功必先承受磨难。

17.Never forget how rare you are. 
勿忽视自身独特之处。

18.Nothing ventured, nothing gained.
不入虎穴焉得虎子。

19.Fortune sides with him who dares. 
不入虎穴焉得虎子。

20.Well done is better than well said. 
说得好不如做得好。