解释：使用毒性大的药物治疗疾病时，病情十成中只能去掉六成就要停药，以免伤害正气。

The stones we pull from the earth carry 400 million years of history—we're merely temporary stewards.

创业是一条充满挑战的道路，但只要有梦想，就有希望。

The stranger is close to us, insofar as we feel between him and ourselves common features of a national, social, occupational, or generally human, nature. He is far from us, insofar as these common features extend beyond him or us, and connect us only because they connect a great many people.

Innovation is not just about creating something new; it's about making a difference in people's lives.

I must confess that I never could see any beauty in her. Her face is too thin; her complexion has no brilliancy; and her features are not at all handsome. Her nose wants character; there is nothing marked in its lines. Her teeth are tolerable, but not out of the common way; and as for her eyes, which have sometimes been called so fine, I could never see anything extraordinary in them.

Don’t wait for opportunities—create them.