The more important goal is using interactive learning to discover the cause of the decline and compare it to issues we face today—natural disasters, environmental problems, and war.

更重要的目标是利用互动式学习来发现减少的原因，并将其与我们今天面临的问题——自然灾害、环境问题和战争——进行比较。

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Of all the world’s major ills – such as war, hunger, and natural disasters – none can quite compare to the millions of baby girls and female fetuses killed by parents who prefer boys.

数以百万计的女婴和女胎被重男轻女的父母杀害！ 所有世界上主要的弊病 —— 如战争、饥饿和自然灾害——没有任何一个可以与之相提并论。

youdao

The risk of a mass cholera outbreak is highest when poverty, war or natural disasters force people to live in crowded conditions without adequate sanitation, according to the Mayo Clinic.

大规模霍乱暴发主要原因贫穷，战争和自然灾害，迫使人们生活在拥挤的条件下，没有足够卫生设备。

youdao

Clearly at the top of the hierarchy of guilty landscapes we would find extermination camps, war zones, battlefields and sites of major disasters.

FORBES: Guilty Landscapes: Oxford, Ystad, Amsterdam and Sodermalm

Few buildings from previous eras survived the twin disasters of the 20th century -- the Great Kanto Earthquake and the U.S. carpet bombing of World War II.

CNN: AFTER THE BANG

Soldiers must endure heavy physical demands, from boot camp and basic training to the rigors of duty, which can include not just war but aiding in natural disasters like hurricane Sandy.

FORBES: The Most Stressful Jobs Of 2013