由于人类活动 地球上的树木已经减少一半

There is good and bad news¹ about trees. The good news is there are seven times more than we thought². Scientists³ thought we had⁴ 400 billion⁵ trees, but we have three trillion. That's a three followed by 12 zeroes⁶. For each person⁷ alive⁸ today, there are 420 trees. A researcher⁹ said¹⁰ these numbers were not good or bad news.

 

The bad news is that we once had six trillion trees. We lost three trillion trees. Europe¹¹ was¹² once a giant¹³ forest¹⁴. Now it is fields¹⁵ and cities. Another 15 billion trees are lost each year. This is a lot more than 100 years ago. The researcher said we must do more to make forests¹⁶ healthy again.

1 news   

n.新闻，消息

参考例句：

• No news is good news.没有消息就是好消息。
• I like reading hot news.我喜欢读热点新闻。

2 thought   

n.想法，思想，思维，思潮，关心，挂念；v.vbl.think的过去式和过去分词

参考例句：

• It was just a thought.这仅仅是一个想法。
• She thought he had a cold.她认为他感冒了。

3 scientists   

n.科学家( scientist的名词复数 )

参考例句：

• Scientists have established a connection between cholesterol levels and heart disease. 科学家已证实胆固醇含量与心脏病之间有关联。
• Scientists disagree about how the universe was created. 科学家对宇宙是怎样形成的有分歧。

4 had   

vbl.have的过去式和过去分词；conj.有

参考例句：

• I just had a good idea!我有个好主意！
• The boy had a small branch of a tree in his hand.这个男孩手上拿一条小树枝。

5 billion   

num.十亿；数以十亿计；大量；一万亿

参考例句：

• A billion is a large number.十亿是个大数目。
• They've spent nearly a billion dollars on it already.他们已经在那上面花了近10亿美元。

6 zeroes   

n.（数字）零( zero的名词复数 )；零点；零度；没有

参考例句：

• The number one thousand is written with a one and three zeroes. 一千这个数字的写法是一个一加三个零。 来自互联网
• Trailing zeroes in the decimal portion are discarded. 在小数部分尾数加0将被废弃。 来自互联网

7 person   

n.人

参考例句：

• I would never trust in that kind of person.我绝不会相信那种人。
• She is the very person I wanted to see.她正是我要见的人。

8 alive   

adj.活着的

参考例句：

• Was the lion alive or dead?这只狮子是死或活？
• He is still alive.他仍然活着。

9 researcher   

n.研究员

参考例句：

• First,he had to establish his credentials as a researcher.首先，他得证明自己做调查员的资格。
• It was an unexpected turn for a researcher.对于一个学术研究者来说，这是一个出乎意料的转机。

10 said   

v.动词say的过去式、过去分词

参考例句：

• He said to me that he could not come.他对我说他不能来。
• He said to his mother that he would do it by himself.他对他的母亲说他将自己独立做那件事。

11 Europe   

n.欧洲

参考例句：

• Have you traveled in Europe?你到欧洲旅行过吗？
• We're planning to visit Europe this summer.我们正打算今年夏天去欧洲旅行。

12 was   

v.(is,am的过去式)是，在

参考例句：

• He said he was right.他说他是正确的。
• He was cold and hungry.他又冷又饿。

13 giant   

adj.庞大的，巨大的；n.巨人，大力士，巨大的怪物

参考例句：

• The whale is the giant of the sea.鲸鱼是海洋中的巨人。
• It is a giant egg.它是一只巨大的蛋。

14 forest   

n.森林，园林，林火；vt.用树林覆盖，植树

参考例句：

• A lion is the king of the forest.狮子是丛林之王。
• I like reading in the forest.我喜欢在树林里读书。

15 fields   

n.田( field的名词复数 )；（作某种用途的）场地；（学习或研究的）领域；运动场

参考例句：

• The only access to the farmhouse is across the fields. 去那农舍的唯一通路是穿过田野。
• We had to make a detour around the flooded fields. 我们只得绕道避开被洪水淹没的田野。

16 forests   

n.森林( forest的名词复数 )；丛林；（森林似的）一丛；一片

参考例句：

• forests planted with beech 山毛榉林
• The two Frenchmen went through strange adventures in the African forests. 两位法国人在非洲森林里经历了种种奇遇。 来自《现代汉英综合大词典》