英语听力精选进阶版 7218

（单词翻译）

Background: 科学家首次揭示了欧洲黑死病鼠疫病源的遗传密码。

黑死病或人们常说的欧洲大瘟疫，曾于14世纪夺走了成千上万欧洲人的生命。

Humans have rarely encountered an enemy as devastating¹ as the bacterium² Yersinia pestis. Between 1347 and 1351 it sparked the Black Death, an infection carried by fleas⁴ that spread rapidly across Europe, killing⁵ around 50 million people.

Now scientists have uncovered some of the genetic⁶ secrets of the plague, thanks to DNA⁷ fragments drilled from the teeth of victims buried in a graveyard⁸ in East London.

The researchers say that all current strains circulating in the world are directly related to the medieval bacterium. And while the infection still kills 2,000 people globally every year, it's much less of a threat because our immune systems have adapted to it.

The scientists say the techniques used to rebuild the genome of the Black Death could now be used to reconstruct other ancient pathogens.

Glossary⁹ 词汇表

rarely encountered 罕见的 

devastating 毁灭性的 

to spark 引起，造成 

a flea³ 虱子 

a fragment 碎片 

a victim 受害者 

a strain 一种（菌）系 

an immune system 免疫系统 

to adapt to 适应 

a pathogen 病原体

Questions:

1: How did the Black Death spread? 

It was carried by fleas.

2: Where did scientists get the DNA from, which helped their research? 

From a graveyard in London.

3: True or False? Modern plague has no connection to the Black Death of the 14th Century. 

False: Researchers say that all modern versions are directly related to the medieval version.

4: What could scientists use the same techniques to do? 

To rebuild other old causes of disease.