They've ______ us$150,000 for the house. Shall we take it?

[　　]

When people ask this question they want to know if you think you are a brave person or a coward.

[　　]

When you are in a very dangerous situation and feel afraid, the body automatically produces a chemical in the blood.

[　　]

Thus the pollution of air would become less important than that of unemployment.

[　　]

In research reported in the science journal Nature, Kendric and his team showed that sheep…

[　　]

Years ago, the experts warned us that the car-ownership explosion would demand a lot more give-and-take from all road users.

[　　]

He kept very calm and did a very courageous thing.

[　　]

People call these strange objects Unidentified Flying Objects（UFO）.

[　　]

After the publication of two most famous papers（论文）, there was not a major university in the world that would not have been glad to have him work for them.

[　　]

One day we may even learn more about the invisible colors around us.

[　　]