We change our environment.
我们改变我们的环境。
People change their environment to make their lives better.
人们改变环境是为了让生活更美好。
There are many waves in which people change their environment.
人们改变环境的浪潮有很多。
Farmers, for example, plow the land before planting seeds.
例如，农民在播种前先犁地。
They use machines to harvest crops, which can affect the environment in many ways.
他们使用机器收割庄稼，这会在许多方面影响环境。
Builders dig beneath the earth to make tunnels through mountains and underground.
建筑工人在地下挖掘隧道，穿过山脉和地下。
They also create large dams to make electricity.
他们还建造大坝来发电。
Such dams change the water flow of a river or stream.
这种大坝改变了河流或小溪的水流。
To make it easier to cross rivers, people build bridges,
为了更容易过河，人们建造桥梁，
which can change the environment of a river in many different ways.
它可以以许多不同的方式改变河流的环境。
Changing our environment makes our lives better, but we should be careful.
改变我们的环境让我们的生活变得更好，但我们应该小心。
Changing the environment can have negative effects on nature.
改变环境会对自然产生负面影响。
We can have more crops by using pesticides.
通过使用杀虫剂，我们可以有更多的作物。
But using too much pesticide can kill animals, plants, and even humans.
但是使用过多的杀虫剂会杀死动物、植物甚至人类。