二、完形填空
"When it comes to the Earth, there's no time to waste," says the Earth Day Network. And that is right. Protecting our environment is very important, and World Earth Day was created in 1970 to make people pay
attention to the protection of our environment. On 22 April, people around the world celebrate Earth Day.
Every year there is a special
. For example, the year 20
16 is "Trees for the Earth", so Earth Day that year was all about planting trees. Their goal was to plant
7.8 billion trees
the next five years.
That's a big goal, and you might wonder
trees are so important. Well, for one, they can help stop climate change. Carbon dioxide (二氧化碳) is a chemical in our atmosphere, but
make too much of it. Each person makes about
2.3 tons a year, which is bad for the environment.
Well, guess what! Trees
carbon dioxide and improve the air quality. Planting new trees is important because people cut down
trees. In
20
15, there were three trillion (万亿) trees in the
, about 1
39 billion in China. But according to Time, the world's total number has been
cut in half since human civilization (文明) began. That's to say, 15 billion trees are cut down every year.
So we need to plant more to replenish (补充) the ones we've lost. One tree can take in 48 pounds (
21.8 kg) of carbon dioxide per year. And it's still one of the cheapest and
ways to get rid of too much carbon dioxide.
(
) 16. A. some
B. no
C. more
D. less
(
) 17. A. name
B. topic
C. song
D. sign
(
) 18. A. for
B. since
C. by
D. in
(
) 19. A. that
B. why
C. whether
D. how
(
) 20. A. humans
B. animals
C. ghosts
D. plants
(
) 21. A. try out
B. put up
C. take in
D. show off
(
) 22. A. countless
B. hopeless
C. useless
D. endless
(
) 23. A. wild
B. world
C. forest
D. space
(
) 24. A. hardly
B. never
C. really
D. almost
(
) 25. A. most
B. best
C. fewest
D. worst