B
[2026 南通市海门区期末]Earth's water has refreshed itself for billions of years with the water cycle. Earth has a lot of water, but most of it isn't fresh water. Earth's fresh water is limited.
◆ The water cycle refreshes water The three parts of the water cycle are evaporation, condensation, and precipitation. 1.
F
. Condensation happens when the vapour cools and changes into water drops. Precipitation happens when the drops fall to Earth's surface. All three parts happen continuously, and they can happen at the same time.
◆ Earth's usable fresh water Earth's water can be found in many places, including underground and in the atmosphere. 2.
D
. Most of the fresh water is in glaciers and polar ice caps, where it is difficult for people to get. Only a small part of Earth's fresh water is in rivers, lakes, and streams. The water cycle helps to keep water usable by refreshing it. But it also causes fresh water to evaporate. As a result, humans and animals can't use it.
◆3.
A
Our use of fresh water is naturally limited. But pollution and overuse make the fresh water even worse. Waste from agriculture and industry can go into the ground and end up in springs. It is harmful to drink polluted water. Waste can also damage waterways, making it hard for water to travel. Even though the water cycle cleans water, pollution in the environment causes water to become polluted over and over again. 4.
B
. People use water for drinking, cleaning and other purposes. Sometimes people waste water or take far more than they need. The whole world uses so much water that the underground water sources run dry.
Humans, animals and plants depend on fresh water. The water cycle renews water all the time. 5.
C
.

A. Problems of Earth's fresh water
B. Overuse also endangers water resources around the world
C. However, we still need to remember that fresh water is limited
D. Although Earth has a lot of water, about 97% of it is salt water
E. Many countries have made laws to protect fresh water from pollution
F. Evaporation happens when water changes into vapour and rises into the air