What is the use of greenhouse gases？
A. They allow energy from the sun to enter but prevent energy from leaving.
B. They allow energy from the sun to leave but prevent energy from entering.
C. They protect the plants.
D. They protect the earth.
查看答案
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.
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
微信支付 
支付宝支付