单项选择题 It's important to remember that nutrients have to work ______, and to take too much of one or another can be useless or even dangerous.

单项选择题 The ______ amongst the world's scientists is that the world is likely to warm up over the next few decades.

单项选择题 Given a relatively ______ sentence of 18 years (others were given suspended death sentences), Chen was later released from jail in consideration of age and poor health.