根据短文理解，完成下列各题。
    In every school there is "top" crowd that sets the pace, while the others follow their lead. For example, if the crowd decides that it is smart to wear bright red sweaters, then very soon everybody is wearing bright red sweaters.
    There is nothing wrong with that, except the fact that for some people bright red sweater is really unsuitable.
    The situation can even become dangerous, if the top crowd decides that it is smart to drink and to drive cars at seventy miles an hour. Then the people who follow the lead are endangering their lives. They are like the sheep being led to the slaughter(屠杀).
    Now it's possible that you have come across situations like these more than once in your life. In fact you probably did something you knew to be wrong one time or another. You may have excused yourself by saying, "Gee, the crowd does it."Well, let the crowd do it, but don't do it yourself. Learn to say "No".
    Develop your own standards(标准)and your own judgment. If you know the crowd is planning something you disagree to, you'd better take the courage to bow out in a polite way. You'll have the satisfaction of standing on your own two feet.

    If you visit the animal shelter in Salinas, California, you'll see huge wood cutouts(剪下的图形) of a dog and a cat. These signs were placed in front of the building to catch people's attention. The supersized cut outs make people curious and encourage them to visit the shelter— and maybe even adopt(收养) a pet. Each year, the Salinas shelter takes in around 2,000 dogs and 2,000 cats. The animals are either strays or are dropped off by people who couldn't take care of them. Of the 4,000 animals, some of them are finally adopted into new homes. Some animals are moved to other shelters. And, unluckily, some cannot be saved because they are too sick or are considered dangerous.   

   Animal shelters provide food, medicine, and a safe place for animals to sleep. But they are not ideal homes. The shelters are loud, and the animals stay in small cages. The people who work at shelters do their best to care for the animals, but the animals do not always get the attention or exercise they need.  

   To prevent so many animals from becoming homeless, pet owners should take care of their pets. One of the best ways to care for pets is to spray or neuter them. This surgery prevents cats and dogs from having more babies. And that reduces the number of homeless animals that end up in shelters.

    Do you still get free plastic bags from the supermarkets? Things have changed.

    China has banned(禁止) free plastic bags in shops and supermarkets, and people have to pay for using plastic bags. The rule started on June 1st. It came because our country tried to make less litter. Making super-thin plastic bags has also been banned.

    The Chinese once used about 3,000,000,000 plastic shopping bags a day, and they have caused the pollution of the environment. The bags have become a main cause of plastic pollution because they are easy to break and people throw them away here and there. So the Chinese people are encouraged to bring their own bags for shopping.

    What kind of shopping bag is the best to bring? Some students in Chongqing have a good idea. They make their own shopping bags. They use old clothes to make cloth bags, and send them to their parents as presents. They also ask their parents and friends to use cloth bags instead of plastic ones. They think it is their duty to protect the environment.

    Earthquakes are hard to predict, but do you know what to do before, during and after an earthquake? Here's some advice:

    Before an earthquake. It's necessary to prepare yourself and your family. All family members should know how to turn off the gas, water and electricity and know useful telephone numbers (120, 110, 119, etc.). Never put heavy things over beds.

    During an earthquake. It's important for each of you to stay calm. If you are indoors, quickly move to a safe place in the room such as under a strong table. The purpose(目的) is to protect yourself from objects. Stay away from windows, large mirrors, heavy furniture and so on. If you're cooking, turn off the gas. If you're outdoors, move to an open area like a playground. Move away from buildings, bridges and trees. If you are driving, stop the car as soon as possible and stay away from bridges and tall buildings.

Stay in your car.

    After an earthquake. Once the shaking has stopped, DO NOT run out of the building at once. It's better to wait and leave when it's safe. Check around you and help the people who are in trouble. If your building is badly broken, leave it. If you smell the gas, get everyone outside and open windows and doors. If you can do it safely, turn off the gas. Report it to the gas company.

    Shanghai University of Engineering Science has become the first university in China to be covered by a 5G network, the university announced on Tuesday.

    Chinese mobile carriers(运营商) are expected to spend 1.2 trillion yuan（US＄176.5 billion） on 5G by 2025,50 percent more than their total 4G investment (投资), Nomura said yesterday. Carriers including China Mobile, China Telecom and China Unicom, are expected to build over 4.9 million 5G base stations by 2025.

    5G is a" game﹣changing" opportunity for carriers as they can explore new business like smart manufacturing, super high definition video and smart driving, instead of just being a "pipeline" for voice and data services.

    China will supply "temporary "5G licenses in several aimed cities this year. Consumers(消费者) will be able to use the first batch of 5G smart﹣phones and tablet computers in the second half. It's the first time that China's top industry regulator clarified the 5G industry timeline, especially the first appearance of 5G phones.

    But 5G services will become accessible to normal consumers later than expected. More work needs to be done to make the 5G industry fully developed, which won't happen until 2020, said UBS recently. New business projects and organizations, rather than normal consumers, will enjoy 5G services at first. The first batch of 5G services will be available to consumers in about 10 cities only.