LinaBell has become popular after making her debut（初次露面）at Shanghai Disney. The topic（话题）of LinaBell has been read over 350 million times on Sina Weibo.

Who is LinaBell? This is how the story begins: while having a great time with his dear friend Mickey Mouse, Duffy said goodbye to him and lost his way. LinaBell found Duffy alone in the forest and helped him find his way back. Then, LinaBell was gifted with a flower.

LinaBell’s souvenirs（纪念品）at Shanghai Disney are very hot. They sell out very fast and sometimes you could only buy from second-hand online stores such as Xianyu at high prices. For example, a mid-sized LinaBell, which sells for 219 yuan, now costs as much as 888 yuan. Products（产品）with LinaBell — including hats, water cups and bags — have become bestsellers on Taobao and JD. com.

However, LinaBell became popular not only because of her cute looks, but also because of her likeable personality（个性）. “LinaBell’s videos keep my worries away from my everyday life. I didn’t believe anyone could love a cartoon character（人物）that much, but after meeting LinaBell, all I can think about is the little pink fox,” a weibo user said．

Why is it called Mars（火星）? Well, Mars is the name of the Roman god of war（罗马战神）. People see the planet（星球）as a symbol of war for thousands of years. It is also known as the Red Planet because of its color. It is red because it’s rich in iron（铁）. Chinese people called it the “fire star” for the same reason.

Scientists was interested in the planet. They first saw Mars in the sky more than 4, 000 years ago. Then, people from all over the world studied the planet. About 200 years ago, scientists started to study pieces of Mars. They broke away and drifted（漂流）through space for millions of years before they got to Earth.

Scientists have learned some things about Mars. For example, Mars is home to a 21-kilometer-tall mountain—the tallest in our solar system（太阳系）. However, Qomolangma, Earth’s highest mountain, is just 9 kilometers tall. Like Earth, Mars has moons. It has two moons named Phobos and Deimos. The Red Planet also has the largest dust storms（沙尘暴）in the solar system. And they can last for months.

Earth is 10 times heavier than Mars. So The Red Planet’s gravity（重力）is only 37 percent as strong as Earth’s, meaning you can jump nearly two times higher on Mars. For the same reason, you are two times heavier on Earth than on Mars.

People know the dangers of fires. It’s good for a family to learn how to stay safe from a fire. Here is some advice.

Put a smoke alarm（警报器）in the house. If there is a fire,     16     The sound tells everyone to leave the house at once.

Make escape plans（逃脱计划）. Everyone should know all the ways out of the house. If there is a fire,     17     Part of the plan is to make sure all the windows can be opened easily.

Buy fire extinguishers（灭火器）in the house. Everyone in the family should know how to use them.

Practice for a fire. They do fire practice because they teach children about fire safety.

    18    

★ Don’t open a hot door! The fire can grow more quickly if you open the door.

★ Stay close to the floor! Smoke can be more dangerous than fire. The best air is near the floor because smoke goes up.

★    19     First, stop! Don’t run! The fire burns faster because of more air. Drop! Fall to the floor. Then roll（打滚）! Turning over and over will make the fire go out. Put a blanket（毯子）around you to keep air away from the fire that may still be on you.

    20     If there is a fire, don’t forget to call 119 for help.