单项选择题

SECTION B PASSAGES
Directions: In this section, you will hear several passages. Listen to the passages carefully and then answer the questions that follow.
听力原文： What makes it rain.9 Rain falls from clouds for the same reason anything falls to Earth. The Earth's gravity pulls it. But every cloud is made of water droplets or ice crystals. Why doesn't rain or snow fall constantly from all clouds? The droplets or ice crystals in clouds are exceedingly small. The effect of gravity on them is minute. Air currents move and lift droplets so that the net downward displacement is zero, even though the droplets are in constant motion.
Droplets and ice crystals behave somewhat like dust in the air made visible in a shaft of sunlight. To the casual observer, dust seems to act in a totally random fashion, moving about chaotically without fixed direction. But in fact dust particles are much larger than water droplets and they finally fall. The cloud droplet of average size is only 1/2500 inch in diameter. It is so small that it would take sixteen hours to fall a mile in perfectly still air, and it does not fall out of moving air at all. Only when the droplet grows to a diameter of 1/125 inch or larger can it fall from the cloud. The average raindrop contains a million times as much water as a tiny cloud droplet. The growth of a cloud droplet to a size large enough to fall out is the cause of rain and other forms of precipitation. This important growth process is called 'coalescence'.
What is the main topic of the passage?
A．The mechanics of rain.
B．The climate of North America.
C．How gravity affects air current.
D．Types of clouds.

A.
听力原文：
B.9
C.
D.
What
E.The
F.
B．The
G.
C．How
H.
D．Types
I.

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单项选择题

听力原文：M: Hi, Sherril.
W: Hello, Fill, how are you?
M: I'm fine, where are you headed?
W: Oh, I'm on my way home from work.
M: I didn't know you had a job.
W: Ya, I work part-time at the supermarket.
M: What do you do there?
W: I work in the produce section, trimming and wrapping fresh fruit and vegetables. I also stock shelves. Sometimes when it really gets busy, I work at the check-ont counter. Have you got a job, Fill?
M: Ya, I do yard work for people. Your know, cutting grass, raking leave and falling weeds, things like that.
W: I'd like doing that. It must be nice to work outdoors.
M: Sometimes it is, except when it rains, or snows or gets too hot or too cold.
W: I guess every job has its drawbacks. There are times when I get pretty tired of carrying things around at my job. But a job is a job. Got to earn money for school.
M: Me too, tuition sure is high, isn't it? Well, I'd better get going. I have to plant some trees for my neighbors this afternoon.
W: Well, don't work too hard, holding down a job, going to class, studying, sometimes can become too much for one person. Take it easy.
M: You too, it was great seeing you, Sherrill.
Where was Sberrill going when Fill met her?
A．To the supermarket.
B．To school.
C．To her home.
D．To work outdoors.

A.
W:
B.
M:
C.
W:
D.
M:
E.
W:
F.
M:
G.
W:
H.
M:
I.
W:
J.
M:
K.
Where
L.To
M.
B．To
N.
C．To
O.
D．To
P.

单项选择题

Speaker A: I wonder if Mary will really come at 7:00. She said she would. Speaker B: ______
A．You can take it easy. Mary always says what she would do.
B．You needn't be worried. Mary is an honest person.
C．Don't worry about it. Her words are as good as gold.
D．Just take it easy. Time will soon come.

A.You
B.
B．You
C.
C．Don't
D.
D．Just
E.