keep a stiff upper lip 不动声色；坚强不屈；意志坚定

【例句】
During the surgery, he needs to keep a stiff upper lip.
动手术时，他必须要坚强些。

It tells us that if you keep a stiff upper lip to chase your goal, you will get successful.
它告诉我们如果你坚定不移的追求你的目标，你就会获得成功。