3 . Rainforests are home to a rich variety of medicinal plants, food, birds and animals. Can you believe that a single bush（灌木丛）in the Amazon may have more species of ants than the whole of Britain! About 480 varieties of trees may be found in just one hectare of rainforest.

Rainforests are the lungs of the planet-storing vast quantities of carbon dioxide and producing a significant amount of the world's oxygen. Rainforests have their own perfect system for ensuring their own survival; the tall trees make a canopy（树冠层）of branches and leaves which protect themselves, smaller plants, and the forest animals from heavy rain, intense dry heat from the sun and strong winds.

Amazingly, the trees grow in such a way that their leaves and branches, although close together, never actually touch those of another tree. Scientists think this is the plants' way to prevent the spread of any tree diseases and make life more difficult for leaf-eating insects like caterpillars. To survive in the forest, animals must climb, jump or fly across the gaps. The ground floor of the forest is not all tangled leaves and bushes, like in films, but is actually fairly clear. It is where dead leaves turn into food for the trees and other forest life.

They are not called rainforests for nothing! Rainforests can generate 75%of their own rain. At least 80 inches of rain a year is normal-and in some areas there may be as much as 430 inches of rain annually. This is real rain-your umbrella may protect you in a shower, but it won't keep you dry if there is a full rainstorm. In just two hours, streams can rise ten to twenty feet. The humidity（湿气）of large rainforests contributes to the formation of rainclouds that may travel to other countries in need of rain.

1. What can we learn about rainforests from the first paragraph?

A．They produce oxygen.	B．They cover a vast area.
C．They are well managed.	D．They are rich in wildlife.

2. Which of the following contributes most to the survival of rainforests?

A．Heavy rains	B．Big trees.
C．Small plants.	D．Forest animals.

3. Why do the leaves and branches of different trees avoid touching each other?

A．For more sunlight.	B．For more growing space.
C．For self-protection.	D．For the detection of insects.

4. What can be a suitable title for the text?

A．Life-Giving Rainforests	B．The Law of the Jungle
C．Animals in the Amazon	D．Weather in Rainforests

4 . 阅读下面文，在空处填入1个适当的单词或括号内单词的正确形式。

China’s Liangzhu Archaeological Site     1    (declare) on the list of World Heritage sites on Saturday by UNESCO’s World Heritage Committee during its 43^rd session in Baku, the capital of Azerbaijan.

The site,     2    is located in Yuhang District in Hangzhou City in China’s eastern Zhejiang Province, showcases the civilization of prehistoric rice agriculture between 3,300 B.C.     3     2,300 B.C. The ruins of ancient Liangzhu city were discovered in 2007, and then large dam sites     4    (surround) the Liangzhu ancient city were unearthed continuously after 2009. It was     5     (official) submitted to UNESCO in 2019, hoping to win     6     (recognize) as a World Cultural Heritage Site. The site     7     (include) archaeological remains and unearthed cultural relics of the Liangzhu Ancient City as well as a wetland that covers     8     area of 908. 89 hectares in a plain river network. It is also found that the Liangzhu ancestors started to use characters about 5 ,000 years ago, 1 ,000 years     9     (early) than previously thought, according to Colin Renfrew, a retired professor of archaeology at the University of Cambridge.

The World Heritage Committee added Liangzhu to the UNESCO list    10     (encourage) better protection of the site, considered to be of “outstanding universal value” to humanity.