Soil     1     (find) nearly everywhere. And it seems unlikely that we would ever lose all the soil on Earth. However,     2     we may lose is the deep and rich agricultural soil because of over-farming, a lack of plant cover off-season and a collection of salt from watering and fertilization (施肥).     3     proper measures, some experts warn, there could be serious agricultural soil problems before the end of this century.

When Zhou Longshan started filming birds 10 years ago at Baiyangdian Lake,     1     major wetland in northern China, he just wanted to record his favorite species—egrets (白鹭).

Then things snowballed. In the following years, the teacher became a bird watcher, a volunteer ranger at the lake, a photographer     2    (document) over 110 bird species, and an     3     (education) popularizing bird-related knowledge among students.

“Sharing bird-protection knowledge with children can make them feel the     4    (beautiful) of their hometown and the importance of birds, and help them cultivate the habit of protecting birds from an early age,” he said.

Growing up in a local village, Zhou,60, has fond childhood memories     5    (associate) with the wetland.

“When I was a child, the water in Baiyangdian was limpid. The fish and aquatic plants in the water could be seen clearly,” he said. “I often caught fish with my friends, rowed boats and drank the lake water     6     I was thirsty.”

Between the 1960s and 1980s,     7    , Baiyangdian suffered severely from industrial pollution. Chemicals poisoned the water and lake beds, decimating the aquatic life. In the 1990s, the lake     8    (near) dried up due to climate change.

When Zhou became a teacher in the 1990s, the stink from the lake could sometimes be smelled from his village. “The lake became stinking, the population and species of fish and birds decreased, and the locals were unwilling to go near the lake,” he recalled.

Since the Xiong’an New Area was established in 2017, Baiyangdian’s rehabilitation and protection activities     9    (improve) greatly. The water quality has improved from Level Ⅴ-the     10    (low) in China’s five-tier water assessment system-to Level Ⅲ.

Zhou will retire in June. “I will continue patrolling the lake and photographing the birds, to contribute to the protection of birds in my hometown,” he said.

Earthquakes are one of the most destructive natural disasters. They can happen just about anywhere. Earthquakes cannot be stopped,     1     your chances of survival are much better if you know what     2     (do) when an earthquake strikes.

If you are in     3     building, drop, cover, and hold on. This     4     (be) the national standard for earthquake safety in the United States. The advice is to get next     5     a strong piece of furniture (家具) so that if a wall falls, it will create something     6     (call) the “triangle of life” to help you survive. Use your     7     (hand) and arms to protect your vital areas like your head and neck. Do not move     8     (immediate) unless it is safe to do so.

Remember that aftershocks are possible at any time and are     9     (likely) after a bigger earthquake. Take good care of     10     (you) when you leave the building.

Rescuers brave chill, race against time to save lives

A bowl of hot beef noodles and a cup of drinking water at a relief camp on Tuesday offered Ma Mengke the warmth he     1     (desperate) needed after a magnitude 6.2 earthquake jolted him and his family members out of sleep around midnight on Monday in Northwest China’s Gansu province.

The makeshift camp,    2     (locate) at the town square, has 102 tents, each of     3     can accommodate eight to nine people. Ma and 1,000 other residents of the county, whose houses     4     (destroy) or damaged in the quake, spent the night in the tents. They received meal boxes provided by local authorities and beef noodles cooked by volunteers from a private company.

Meanwhile, rescue teams     5     (brave) the winter chill to continue their search for    6     (survivor) The substantial difference between day and night temperatures in Jishishan made the search and rescue operation     7     (challenge).

Wang Duo, a team leader from the Gansu Houtian Disaster Rescue Center, said the minimum temperature is around -10 C, and those trapped under the rubble of collapsed buildings are     8     great risk.

Liu Xuefeng, deputy head of Gansu’s Forest Firefighting Department, said his 200-member team was among     9     first responders. The team arrived in Jishishan county as early as 2 am on Tuesday.

At the local hospitals, doctors also raced against time to save lives. Currently, there are six medical teams comprising over 40 personnel     10     (provide) support at the People’s Hospital of Linxia, while nurses have been mobilized from other hospitals.

A study shows 176 bird species have been found to build nests with human litter, such as plastic bags and fishing nets.     1     worries the scientists is that such materials can harm chicks and even adult birds. The study     2     (review) research covering almost 35,000 nests and finds that birds use human-made materials in nests on all continents except Antarctica. While such behaviour     3     (observe) as early as in the 1830s, in recent years it has undoubtedly increased.

There are     1     (vary) causes of water pollution. Large amounts of industrial waste poison the water after they enter water bodies. Moreover, animal and human waste pollutes the water. Water pollution is also caused by     2     (poison) chemicals used in agriculture.

    3     (pollute) water bodies not only do harm to animals and plants; they also have a long-lasting effect     4     humans. For example, in many parts of the world, the poor quality of the local     5     (drink) water gives rise     6     public health problems.

    7     (prevent) further damage     8     water bodies, it is necessary to take some measures. First, we must draw public attention     9    the problem. Second, more strict laws should    10     (pass) to help reduce water pollution. Third, we can volunteer to take part in clean-up activities.

The color of the ocean has changed     1     (great) recently and human-caused climate change is responsible, according to     2     new study.

More than 56% of the world’s oceans have changed color,     3     cannot be explained, said a team of researchers, led by scientists from the National Oceanography Center in the UK.

Tropical (热带的) oceans close to the equator     4     (become) greener in the last 20 years, according to the study     5     (publish) in the journal Nature.

“    6     is not clear exactly how these ecosystems are changing”, said Stephanie from the Center for Global Change Science. “All changes are causing an imbalance in the natural organization of ecosystems. Such imbalance will only get     7     (bad) over time if our oceans keep heating,” she told CNN.

Though the researchers are still working to understand exactly     8     the changes mean, they said what is clear is that the changes are being driven     9     human behavior.

The researchers studied changes in ocean color from space by     10     (watch) how much green or blue light is reflected from the surface of the sea.