Plants are flowering faster than scientists predicted（预测）in reaction to climate change, which could have long damaging effects on food chains and ecosystems.
Global warming is having a great effect on hundreds of plant and animal species around the world, changing some living patterns, scientists say.
Increased carbon dioxide（CO2）in the air from burning coal and oil can have an effect on how plants produce oxygen, while higher temperatures and changeable rainfall patterns can change their patterns of growth.
“Predicting species’ reaction to climate change is a major challenge in ecology,” said the researches of several U.S. universities. They said plants had been the key object of study because their reaction to climate change could have an effect on food chains and ecosystem services.
The study, published on the Nature website, uses the findings from plant life cycle studies and experiments across four continents and 1,634 species. It found that some experiments had underestimated（低估）the speed of flowering by 8.5 times and leafing by 4 times.
“Across all species, the experiments under-predicted the speed of the advance — for both leafing and flowering — that results from temperature increases,” the study said.
The design of future experiments may need to be improved to better predict how plants will react to climate change, it said.
Plants are necessary for life on the Earth. They are the base of the food chain, using photosynthesis（光合作用）to produce sugar from carbon dioxide and water. They let out oxygen which is needed by nearly every organism on the planet.
Scientists believe the world’s average temperature has risen by about 0.8℃since 1900, and nearly 0.2℃ every ten years since 1979.
So far, efforts to cut emissions（排放）of planet-warming greenhouse gases are not seen as enough to prevent the Earth heating up beyond 2℃ this century — a point scientists say will bring the danger of a changeable climate in which weather extremes are common, leading to drought, floods, crop failures and rising sea levels.
小题1:What is the key information the author wants to give in Paragraph 1?

A．Plants’ reaction to weather could have damaging effects on ecosystem.

B．The increasing speed of flowering is beyond scientists’ expectation.

C．Climate change leads to the change of food production patterns.

D．Food chains have been seriously damaged because of weather.

小题2:We can learn from the study published on the Nature website that ______.

A．plants’ flowering is 8.5 times faster than leafing

B．there are 1,634 plant species on the four continents

C．scientists should improve the design of the experiments

D．the experiments failed to predict how plants react to climate change

小题3:Scientists pay special attention to the study of plants because _______.

A．they can prove the climate change clearly

B．they are very important in the food chains

C．they play a leading role in reducing global warming

D．they are growing and flowering much faster than before

小题4:What can be inferred from the last two paragraphs about the world’s temperature?

A．It has risen nearly 0.2℃ since 1979.

B．Its change will lead to weather extremes.

C．It is 0.8℃ higher in 1979 than that of 1990.

D．It needs to be controlled within 2℃ in this century.

Colorful hair speaks more about beauty. Now it becomes popular and people are dyeing their hair to make it different. Dyeing hair with natural products is good for health while dyeing with chemicals is harmful. Researches have found that dyeing hair with chemicals can make people have cancer.
　　Lead(铅)is very harmful for the human body and it is used in most hair dyes. Since the base of hair is the scalp(头皮)，you may have allergic reaction(过敏反应).
　　While dyeing your hair it is important to take some safety measures. You can follow them even when you are applying(涂) dye on your hair at home.
? It is better to apply hair dye for a few minutes. If you leave your hair with dye, longer than the necessary time，then you may get some skin problems.
? Don't forget to wear gloves while applying dye on the hair. This will protect the skin of your
hands.
? After applying hair dye it is important to wash your hair with water.
? Hair dyes are made of chemicals. If you mix different hair dyes ,there may be chemical reaction.  So, It is not a good idea to mix different hair dyes at the same time.
? Finally all the bags of hair dyes carry the directions(说明书 ) Try to follow them very carefully. This will lower the chance of allergic reaction.
小题1:What do most hair dyes contain? 

A．Iron

B．Silk.

C．Lead

D．Gold

小题2:What does the underlined word "it" refer to?

A．Beauty

B．Health.

C．Blackhair.

D．Colorfulhair.

小题3:How can you make the chance of allergic reaction lower? 

A．Dyewithchemicaldye.

B．Mixdifferenthairdyesatthesametime.

C．Leaveyourhairwithdyelonger.

D．Doasthedirectionstellyou.

小题4:From the passage，we can infer that _____ 

A．amanwhooftendyeshishairmayhavecancer

B．amanwhodoesn’tliketowashhairmayhavecancer

C．leadisgoodforthehumanbody

D．wemustn'tdyeourhair

小题5:What's the main idea of the passage? 

A．Howtodyeourhair.

B．Dyeinghairisharmful.

C．Tipsoilprotectingourhair.

D．Makeourhairmorebeautiful.