Diets have changed in China— and so too has its top crop. Since 2011, the country 【小题1】 (grow) more com than rice. Corn 【小题2】 (produce) has jumped nearly 125 percent over the past 25 years, while rice has increased only 7 percent.

A taste for meat is 【小题3】 (actual) behind the change: An important part of its corn is used to feed chickens, pigs, and cattle. Another reason for corn's rise: The government encourages farmers 【小题4】 (grow) corn instead of rice to improve water quality. Corn uses less water than rice and creates less fertilizer (化肥) runoff. This switch has decreased 【小题5】 (pollute) in the country's major lakes and reservoirs and made drinking water safer for people.

According to the World Bank, China accounts for about 30 percent of total 【小题6】 (globe) fertilizer consumption. The Chinese Ministry of Agriculture finds I that between 2005— when the government 【小题7】 (start) a soil-testing program that gives specific fertilizer farmers 【小题8】 (recommend)— and 2011, fertilizer use dropped by 7.7 million tons, 【小题9】 prevented the emission (排放) of 51.8 million tons of carbon dioxide. China’s approach to protecting its environment while 【小题10】 (feed) its citizens “offers useful lessons for agriculture and food policymakers worldwide,” says the bank’s Juergen Voegele.

Every day people throw away a lot of household garbage — paper, cans, kitchen waste, used batteries and glass without 【小题1】(sort) it. There are many problems 【小题2】(cause) by unsorted garbage. On one hand, it’s 【小题3】 great waste of resources. On the other hand, the disposal of unsorted garbage can cause serious environmental pollution, 【小题4】 does harm to people’s health. Now our government has realized the importance of garbage sorting. So far many 【小题5】(activity) have been held to teach people how to sort garbage 【小题6】(proper).

People in cities, like Beijing and Shanghai, are required to sort garbage into four categories — kitchen waste, 【小题7】(danger) waste, recyclable waste and other waste. Also, they can get certain points for sorting their garbage. When they accumulate enough points, they can go to the community 【小题8】(exchange) them for some gifts of daily use. However, still a lot of people in China lack the awareness 【小题9】 garbage sorting. Changing people’s mindsets and habits will take a long time. But once one person 【小题10】(develop) the habit of garbage sorting, more may be influenced to do the same.

Every year, butterfly(蝴蝶) lovers in California go out in November to count monarch butterflies. They 【小题1】(get) a worrying result from their fall monarch count in 2018—【小题2】 number of monarchs had dropped by 86% since 2017.

The orange and black monarch butterflies are famous 【小题3】 their long migrations(迁徙)—they fly thousands of miles every year. In the spring and summer they fly north; in the fall they fly south again.

Monarchs, like most butterflies, are 【小题4】(terrible) important for plants. They help create more plants by spreading pollen(花粉) between plants. In turn, monarchs depend on plants for food. And they depend completely on a plant called milkweed 【小题5】(lay) their eggs.

But monarchs have been facing growing problems for years. As more and more wild land has been turned into large farms, the monarchs have had trouble 【小题6】(find) enough milkweed. Many farms also use chemicals 【小题7】 will kill insects in order to protect their plants. These chemicals also affect monarchs. Besides, pollution has made milkweed less 【小题8】(health) for the monarchs than it used to be.

Scientists say monarchs will be in danger of dying out in the next 20 years if nothing 【小题9】(do) to save them.

【小题10】(thing) that people can do to help include planting milkweed, controlling the use of chemicals, protecting wild areas, and planting trees.