industrial machinery. It is thought that they are capitalising on their predators(天敌)fleeing to quieter areas.

1. According to Dr Dominoni's study, what causes robins to sing so much?

A.The breeding season.

B.The light in modern life.

C.The dangerous environment.

D.The noise from heavy machinery.

2.What is the researchers' concern over the increase of birds' song output?

A.The environment might be polluted.

B.The birds' health might be damaged.

C.The industry cost might be increased.

D.The people's hearing might be affected.

3.What does the underlined word"nocturnal"in Paragraph 5 mean?

A.Active at night. B.Inactive at night.

C.Active during the day. D.Inactive during the day.

4.Why do some birds thrive in noisy environments?

A.Because there are fewer dangers.

B.Because there is more food to eat.

C.Because there is less light pollution.

D.Because there are more places to take shelter.

答案

1.B　2.B　3.A　4.A　

　　No one is sure how the ancient Egyptians built the pyramids near Cairo. But a new study suggests they used a little rock'n'roll. Long-ago builders could have attached wooden poles to the stones and rolled them across the sand, the scientists say.

"Technically, I think what they're proposing is possible, "physicist Daniel Bonn said.