1 A：inflexible

　　2 D：become extinct

　　3 B：end

　　4 D：compete

　　5 A：simple

　　6 C：fundamental

　　7 A: polluted

　　8 C：break

　　9 A：wiped

　　10 B：importance

　　11 C：undamaged

　　12 A：doubtful

　　13 D：approved

　　14 B：spread

　　15 B：cautious

23.　How are black holes formed?

　　24.　What are black holes made of?

　　25.　What happens to the objects around a black hole?

　　26.　Is there proof that black holes really exist?

　　27.　an explosion of huge stars

　　28.　the tiniest particle

　　29.　the same amount of mass

　　30.　the existence of black holes

　　阅读判断

　　参考答案

　　16：MIT researchers carry out the study to illustrate an ancient Chinese proverb.

　　Wrong

　　17: Silk’s strength comes from its weak hydrogen bonds working together.

　　Right

　　18: Biologists and engineers are interested in understanding natural silks because they are very light and brittle.

　　Wrong

　　19: If the hydrogen bonds break due to external forces, they break fast.

　　Wrong

　　20: The MIT team had tried different materials before they studied natural silk in the research.

　　Not mentioned

　　21: Carbon nanotubes are currently the most popular topic in material science.

　　Right

　　22: It is indicated that materials stronger than natural silk can be expected in

　　Right

31、D Creativity of the forecaster

　　32、C weather conditions stay stable

　　33、A weather features are constant for a long period of time.

　　34、B the current weather scenario is different from the analog.

　　35、C the climatology method and analog method

　　36.B

　　37.A

　　38.D

　　39.C

　　40.C

参考答案：EBCAF