What does the man advise the woman to do before the trip?
A. Improve her English.
Brush up on her French.
C. Prepare more things.
D. Prepare her passport.
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Which of the following statements is true?
A. When sunlight strikes an object, all the energy is absorbed.
B. When sunlight strikes an object, all the energy is reflected.
C. Snow reflects all the energy from the sun.
D. Snow contributes to the low temperatures of winter.
What does the speaker say about the symptoms of the common cold?
A. Blood becomes slow.
B. Temperatures decreases.
C. They show our body is fighting the virus.
D. Have a headache.
The Stamp Act______.
A. was an act about selling stamps at prices from a few cents to almost a dollar
B. required that all commercial and legal documents in America have stamps on them
C. was one of the causes of the American Revolution
D. chiefly affected business people who felt it would ruin their businesses
听力原文: We experience different forms of the Sun's energy every day. We can see its light and feel its warmth. The Sun is the major source of evaporation of water from the oceans and lakes. Sunlight also provides the energy used by green plants to make their own food. These green plants then provide food for all organisms on the Earth.
Much of the energy that comes from the Sun never reaches the Earth's surface. It is either reflected or absorbed by the gases in the upper atmosphere. Of the energy that reaches the lower atmosphere, 30% is reflected by clouds or the Earth's surface. The remaining 70% warms the surface of the planet, causes water to evaporate, and provides energy for the water cycle and weather. Only a tiny part, approximately 0.023%, is actually used by green plants to produce food.
Many gases found in the atmosphere actually reflect heat energy escaping from the Earth's surface back to the Earth. These gases act like the glass of a greenhouse in that they allow energy from the Sun to enter but prevent energy from leaving. They are therefore called greenhouse gases.
When sunlight strikes an object, some of the energy is absorbed and some is reflected. The amount reflected depends on the surface. For example, you've probably noticed how bright snow is when sunlight falls on it. Snow reflects most of the energy from the Sun, so it contributes to the low temperatures of winter. Dark-colored surfaces, such as dark soil or forest, absorb more energy and help warm the surrounding air.
What is the major source of evaporation of water from the oceans and lakes?
A. The moon.
B. The sun.
C. The star.
D. The earth.