2018--2019学年人教版选修七Unit 4 Sharing reading课时作业(6)
2018--2019学年人教版选修七Unit 4 Sharing reading课时作业(6)第2页

9.A.disturbed B.supported C.embarrassed D.attracted

10.A.end B.past C.course D.distance

11.A.showing B.acting C.saying D.wanting

12.A.exercise B.explore C.express D.explain

13.A.print B.write C.sign D.count

14.A.slow B.steady C.normal D.obvious

15.A.chair B.sponsor C.attend D.organize

16.A.missed B.passed C.gave up D.registered for

17.A.prohibited B.welcomed C.ignored D.repeated

18.A.Lastly B.Thus C.Instead D.However

19.A.required B.caused C.allowed D.expected

20.A.easy B.popular C.quick D.new

答案

1.A 2.B 3.C 4.D 5.A 6.C 7.B 8.A 9.D 10.B 11.D 12.B 13.C 14.A 15.C 16.D 17.A 18.C 19.B 20.D 

第二节 阅读理解

  When a leafy plant is under attack, it doesn't sit quietly. Back in 1983, two scientists, Jack Schultz and Ian Baldwin, reported that young maple trees getting bitten by insects send out a particular smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be an alarm. What the plants pump through the air is a mixture of chemicals known as volatile organic compounds, VOCs for short.

  Scientists have found that all kinds of plants give out VOCs when being attacked. It's a plant's way of crying out. But is anyone listening? Apparently. Because we can watch the neighbors react.

Some plants pump out smelly chemicals to keep insects away. But others do double duty. They pump out perfumes designed to attract different insects who are natural enemies to the attackers. Once they arrive, the tables are turned. The attacker who was lunching now becomes lunch.