A person who has never tasted bitter won’t know ______ sweet is.
—Americans spend more on health care than most other people .— You’re right . But a new study shows that life in the United States is falling .
--- Will you waste your time and money on that? --- Certainly ________.
_________ to 100℃, water will boil.
The traffic is heavy these days. I ________ arrive a bit late, so could you save me a place?
The consequences of our actions are unbelievably complicated and diverse _______ predicting the future is a very difficult business indeed.