It is easier to float in the ocean than it is to float in a swimming pool. Do you know why?
Ocean water is full of salt— and salt water can hold up more weigh than fresh water. See for yourself!
You Will Need:
● 3 cups of warm water
● Measuring cup (量杯)
● Wide-mouthed jar
● Salt
● Spoon
● Raw (生的)potato
You Will Do:
1. Pour 1.5 cups of warm water into the jar.
2. Add 1/3 cup of salt.
3. Stir(攪拌) until the salt is completely dissolved.
4. Add another 1.5 cups of water. Pour it slowly over the back of the spoon into the jar so that the two liquid will not mix together.
5. Gently place the potato into the jar. Do not drop it.
What Will Happen:
The potato will sink— but only halfway!
Why?
Salt water is heavier than fresh water, so it will stay on the bottom. The fresh water will remain on top.
The potato is heavier than the fresh water, but it is lighter than the salt water. That is why the potato will sink halfway down.
小題1:In the experiment, what should you do right after you pour the water over the spoon?
A．Add the salt to the water.B．Stir the salt into the water.
C．Place the potato in the jar.D．Pour warm water into thejar.
小題2:In Step 4 of the experiment, why do you pour the water over the spoon “slowly”?
A．It is easier to see what you are doing.
B．It pushes the fresh water to the bottom.
C．It will keep the water from coming out.
D．It will keep the liquids from mixing together.
小題3:In which step of the experiment do you add the salt?
A．Step 1B．Step 2C．Step 3D．Step 4
小題4:What does the underlined word “gently” mean?
A．CarefullyB．QuicklyC．SecretlyD．Silently

小題1:C
小題2:D
小題3:B
小題4:A

試題分析：本文介紹了一個(gè)證明鹽水的浮力比淡水的浮力大的實(shí)驗(yàn)。
小題1:C 細(xì)節(jié)題。根據(jù)You Will Do:中的5 Gently place the potato into the jar. Do not drop it說(shuō)明C正確。
小題2:D 細(xì)節(jié)題。根據(jù)Add another 1.5 cups of water. Pour it slowly over the back of the spoon into the jar so that the two liquid will not mix together中的so that the two liquid will not mix together指這兩種液體不要混在一起。故D正確。
小題3:B 細(xì)節(jié)題。根據(jù)You Will Do:中的2 Add 1/3 cup of salt.說(shuō)明B正確。
小題4:A 推理題。根據(jù)Gently place the potato into the jar. Do not drop it中的Do not drop it不要扔下去，說(shuō)明要輕輕地放，故A正確。
點(diǎn)評(píng)：本文考查的細(xì)節(jié)題特多，答題時(shí)在文章找到對(duì)應(yīng)的地方，用筆進(jìn)行標(biāo)記，這有利于后期有時(shí)間檢查時(shí)可以立刻找到答案的位置。仔細(xì)理解作者所講的意思，再結(jié)合選項(xiàng)，通過(guò)排除法和自己對(duì)全文的把握，選出正確答案。
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科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

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科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

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Much of the water we use comes from snow. Melting snow provides water for rivers, electric power centers and agricultural crops. In the western United States, mountain snow provides up to 75% of all surface water supplies.
Snowfall helps to protect plants and some wild animals from cold, winter weather. Fresh snow is made largely of air trapped among the snow crystals. Because the air has trouble moving, the movement of heat is greatly reduced.
Snow also is known to influence the movement of sound waves. When there is fresh snow on the ground, the surface of the snow takes in, or absorbs, sound waves. However, snow can become hard and flat as it becomes older or if there have been strong winds. Then the snow's surface will help to send back sound waves. Under these conditions, sounds may seem clearer and travel farther.
Generally, the color of snow and ice appears white. This is because the light we see from the sun is white. Most natural materials take in some sunlight. This gives them their color. However, when light travels from air to snow, some light is sent back, or reflected. Snow crystals have many surfaces to reflect sunlight. Yet the snow does take in a little sunlight. It is this light that gives snow its white appearance.
Sometimes, snow or ice may appear to be blue. The blue light is the product of a long travel path through the snow or ice. In simple terms, think of snow or ice as a filter. A filter is designed to reject some substances, while permitting others to pass through. In the case of snow, all the light makes it through if the snow is only a centimeter thick. If it is a meter or more thick, however, blue light often can be seen.
小題1:How many functions of snow are discussed in the passage?
A．OneB．TwoC．ThreeD．Four
小題2:Why does snowfall help to protect plants from cold?
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B．Because snow crystals have air in them.
C．Because snow crystals are easy to blow away.
D．Because snow crystals send out heat when melting.
小題3:It can be inferred that ______.
A．hard snow is better in protecting wild animals than fresh snow
B．fresh snow is better in sending sound waves than hard snow
C．fresh snow is better in taking in sound waves than hard snow
D．hard snow provides less water than fresh snow
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Left-Handers’ Day
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Another problem is that many people have considered it bad to be left-handed. Some teachers and parents have tried to force children who used their left hands to use their right ones instead.
Scientists do not really know why some people are left-handed. They have believed the reason is genetic.They say the gene（基因） increases the chance of being left-handed. It appears to play an important part in deciding which part of the brain controls different activities. In right-handed people, the left side of the brain usually controls speech and language. The right side controls feelings. However, the opposite is often true in left-handed people.
Scientists believe the gene is responsible for this. The gene showed a link with left-handedness in nine to twelve percent of the population.
About ten percent of people around the world are left-handed.
小題1:International Left-handers’ Day aims to（目的是） bring attention to_________.
A．the right-handers
B．the everyday problems
C．the people who have some difficulty using equipment and tools
D．the everyday problems of people who use their left hands
小題2:How many problems of people who use their left hands are mentioned?
A．One.B．Two.C．Three.D．Four.
小題3:As to why some people are left-handed, scientists believe the reason is________.
A．habitsB．geneticsC．parentsD．birthplaces
小題4:______of people around the world are left-handers.
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