1 . 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. |
| A．Heavy rains | B．Big trees. |
| C．Small plants. | D．Forest animals. |
| A．For more sunlight. | B．For more growing space. |
| C．For self-protection. | D．For the detection of insects. |
| A．Life-Giving Rainforests | B．The Law of the Jungle |
| C．Animals in the Amazon | D．Weather in Rainforests |
2 . America's Most Beautiful Places to Visit in Spring
Washington, D.C.
Every spring, Washington, D.C.is blanketed in pink with cherry blossoms. To celebrate the event, come to the National Cherry Blossom Festival, which takes place from the last week in March to the second week in April. You can view the flowers or take part in festival events.
Charleston, South Carolina
No list of beautiful spring cities would be complete without mention of Charleston, South Carolina. Delight in hanging plants, cobblestone streets, and historical castles. And because of year-round pleasant temperatures, you might even hit a beach day in March or April.
North Cascades National Park, Washington
The North Cascades is home to everything from mountains to forests to grassland, and the scenery changes seasonally. In spring—the snow disappears to bring strong waterfalls, and wildflowers spot the land. Different areas will present totally unique plants, so give yourself a few days to take in the sights.
Central Park, New York
New York is the city that never sleeps, no matter what the season, but springtime is the best time to take a walk through Central Park. It is one of the most filmed locations in the world. A spring time promises walks past Victorian houses, a brief visit to ancient shops, and of course long walks by the lake.
1. Which is the best time to visit Washington, D.C.?| A．March 15. | B．April 1. |
| C．March 8. | D．April 28. |
| A．cherry blossoms and various celebrations |
| B．pleasant weather and historical castles |
| C．strong waterfalls and wild flowers |
| D．Victorian houses, old shops, and long walks |
| A．Central Park, New York | B．North Cascades National Park |
| C．Charleston | D．Washington, D.C. |
