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：本文介紹了一個證明鹽水的浮力比淡水的浮力大的實驗。
小題1:C 細節(jié)題。根據(jù)You Will Do:中的5 Gently place the potato into the jar. Do not drop it說明C正確。
小題2:D 細節(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 細節(jié)題。根據(jù)You Will Do:中的2 Add 1/3 cup of salt.說明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，說明要輕輕地放，故A正確。
點評：本文考查的細節(jié)題特多，答題時在文章找到對應的地方，用筆進行標記，這有利于后期有時間檢查時可以立刻找到答案的位置。仔細理解作者所講的意思，再結(jié)合選項，通過排除法和自己對全文的把握，選出正確答案。
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科目：高中英語 來源：不詳 題型：閱讀理解

Michael Fish may soon be replaced as a weather forecaster by the shark (鯊魚).
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A．a(chǎn) short-story collection
B．a(chǎn) popular science magazine
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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.
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C．Because snow crystals are easy to blow away.
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小題3:It can be inferred that ______.
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Left-Handers’ Day
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