题目内容

Infrared thermometers(红外温度计), or temperature guns, have been widely used to detect(检测)the early symptoms of COVID-19. They allow us to measure(测量)temperatures quickly. How do these thermometers work?

They determine temperature by measuring the energy coming from your skin (皮肤). Everything in nature has molecules (分子) inside of it that are always moving around. This include our skin. The higher the temperature is, the faster the molecules move. The molecules give off infrared light while moving.

This kind of light can be focused or absorbed(吸收). The thermometers use a lens(镜头)to focus infrared light from the skin onto a detector called a thermopile(热电堆). The thermopile absorbs the infrared radiation and turns it into heat. The electronic sensors inside the thermometers can measure the heat and read the temperature of the skin after making some calculations (计算).

However, you might sometimes find that the results aren’t always accurate (准确的). It depend on how these devices are used. For example, how far away they are held from the body, how steadily they are held and for how long. Factors such as make-up and sweat will also affect the results.

1.Temperature guns, have been widely used to detect (检测)the early symptoms of____________.

A.COVID-17. B.COVID-18. C.COVID-19. D.COVID-20.

2.They determine temperature by measuring the energy coming from your____________.

A.skin B.head C.face D.foot

3.The electronic sensors inside the thermometers can measure the heat and read the____________ of the skin.

A.color B.temperature C.light D.structure

4.Which one of the following might not affect the accurate results?

A.The thermometers is too far from the body.

B.The thermometers is held for very long.

C.Make-up and sweat.

D.The thermometer is held steadily at the right time.

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Gulangyu,a beautiful island in Xiamen,Fujian,was successfully listed in the UNESCO World Heritage(世界文化遗产)on July 8th,2017.It’s not only the pride of my hometown,but also the pride of the whole nation.

Gulangyu is separated from Xiamen by the 600-metre-wide Egret River(鹭江), with an area of 1.91 square kilometers. It’s like a garden on the water. You can go there only by ships. Cars, buses and bikes are not allowed to run on the island. It is so quiet that wherever you go, you can hear the sound of playing the piano. As a result of this, it is called “the island of music”.

The first name of the island was Yuanzhouzi. In the Ming Dynasty it was changed as Gulangyu, meaning “drum waves”.Because the holes in the southwestern reefs (暗礁)hit by the waves make sounds like the drum beating.

Today, Gulangyu is listed as one of the nation’s major travelling places of interest here include the Sunlight Rock,Shuzhuang Park,Gangzihou Bathing Beach and Memorial Hall to Zheng Chenggong,which are visited by millions of people from all parts of the country and the world.What’s more,the buildings and food are popular with visitors.

Therefore, I hope our government can protect the fairyland well,especially the environment.

1.Where does the writer come from?_____

2.How big is Gulangyu?_____

3.Can you ride bicycles on the island?_____

4.Why is Gulangyu also called “the island of music”? _____

5.How many places of inerest in Gulangyu are mentioned in this passage?_____

Having clean hands is important because people often use their hands to touch their eyes, noses and mouths. Touching these areas gives germs (细菌) the chance to go into the body.

“Washing hands is an important lifetime habit for staying healthy,” doctors say. Cleaning your hands is one of the best and also the easiest ways to protect yourself from getting sick. But it takes more than just placing your hands under running water for a few seconds.

How can you make sure you are washing your hands correctly? Here are five easy steps you can take to wash your hands.

● Wet your hands with warm water.

● Lather up with soap. Be sure to lather the backs of your hands, between your fingers, and under your nails.

● Rub your hands for at least 20 seconds-about the time it takes to sing “Happy Birthday” song twice.

● Wash your hands well under warm, running water.

● Dry your hands with a clean towel.

You should always wash your hands before meals after eating, after using the toilet, after returning home, after touching animals ...

We hope you can have the habit of hand washing.

1.Why should we keep our hands clean?

A.Because things are mostly touched by hands.

B.Because it is easy for us to do in our daily lives.

C.Because germs can get into our body through hands.

D.Because cleaning hands can protect ourselves from getting sick.

2.What should we do after we wet our hands with warm water?

A. B. C. D.

3.Which of the following is TRUE according to the passage?

A.We should use running water to wash our hands.

B.We should wash our hands before touching animals.

C.We should use warm water to kill the germs on ours hands.

D.We should sing the song “Happy birthday” while washing hands.

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