Ⅰ. 阅读理解(每小题2.5分,共10分)
The Antarctic's snow-white environment is going green and facing other unexpected threats.
Scientists say that as temperatures go up in the polar areas, invading (侵袭) plants and insects, including the flies, cause a major threat.
More and more of these invaders, in the form of larvae (幼虫) or seeds, are surviving in coastal areas around the South Pole, where the temperature has risen by almost 3 °C over the past five decades. Glaciers have melted, exposing more land which has been occupied by mosses that have been found to be growing more quickly and thickly than ever before—providing potential green homes for invaders.
"The common houseflies are a perfect example of the problem the Antarctic now faces from invading species," said Dominic Hodgson of the British Antarctic Survey. "They arrive by
ship, where they exist in kitchens. They now have an increasing chance of surviving in the Antarctic as it warms up, and that is a worry. Insects like the houseflies carry bacteria that could have a deadly effect on native life forms."
The Antarctic has several native species of insects. Together with its native mosses, these are now under increased threat from three major sources: visiting scientists, increasing number of tourists and global warming. However, it is global warming that is the main driver of the "greening" of the Antarctic.
In the 2015—2016 travel season, more than 38,000 tourists visited the Antarctic. "These tourists are often very careful about not leaving waste. But they could carry seeds or larvae on their boots when they set foot on the Antarctic," said Dominic.
More and more invading insects and plants have been found on the Antarctic and have required removal. "The insects and plants that are native to the Antarctic have survived there for thousands of years," said Dominic. "We have to act now if we want to save the environment."
1. What does the underlined word "mosses" in Paragraph 3 refer to? ()
A. Houseflies. B. Coastal areas.
C. A kind of plant. D. A kind of animal.
2. What do we know about the houseflies in the Antarctic? ()
A. They are native to the Antarctic.
B. They will die out because of the freezing weather.
C. They come to the Antarctic from nearby islands on their own.
D. They could severely influence the native species of the Antarctic.
3. What is the main cause of the Antarctic going green? ()
A. The arrival of scientists.
B. The increasing number of visitors.
C. The rapid spread of native plants.
D. The rising temperature around the world.
4. What's the best title for the text? ()
A. The Antarctic Is Becoming Green and Energetic
B. Various Threats Are Putting the Antarctic at Risk
C. More and More Scientists Get to Explore the Antarctic
D. Global Warming Causes the Temperature in the Antarctic to Go Up

语篇解读 本文是一篇说明文。文章讲述的是由于全球气温上升等原因,各种各样的威胁正置南极地区于危险之中。
1. C 词义猜测题。根据第三段中的"that have been found to be growing... green homes for invaders"可知,画线词指的是一种植物,故选 C。
2. D 细节理解题。根据第四段最后一句可知,像家蝇一样的昆虫所携带的细菌会严重影响南极地区当地的物种。故选 D。
3. D 细节理解题。根据第五段最后一句可知,南极地区变绿的主要原因是全球气候变暖。故选 D。
4. B 标题归纳题。通读全文可知,本文讲述的是各种各样的威胁正置南极地区于危险之中。故 B 项最适合作文章标题。故选 B。