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问题 选择题

有些植物到冬天会落叶，这是因为（　　）

A．防止二氧化碳进入

B．防止水分散失过多

C．防止水分吸收

D．防止二氧化碳排出

答案

植物的蒸腾作用是指植物体内的水分通过叶片的气孔以水蒸气的形式散发到大气中去的一个过程，蒸腾作用能蒸发掉植物体内大量的水分，带走植物体内的热量，降低植物体的温度，叶片是蒸腾作用的主要部位．由于冬天温度低，降雨也少，植物通过根吸收的水分减少，所以在秋天大部分树木叶片要脱落，以降低蒸腾作用，减少植物体内热量的散失以及水分的流失，以度过寒冷、干旱的冬季．故B是正确的．

故选：B

单项选择题

在我国，股票账户可以买卖的对象有( )。

A．股票

B．债券

C．基金

D．以上都可以
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阅读理解
阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项标号涂黑。
A
HIGHFIELD COMPREHENSIVE SCHOOL
SCHOOL REPORT
Form Teacher: G. Baker            Pupil’s Name:  Simon Watkins
Term:        Summer 2010       Form:        Ⅳ B
Subject
Exam
Class work
Comments
English
59
61
Simon has reached a satisfactory standard but now needs to apply himself with more determination.
Mathematics
77
85
Sound work and progress throughout the year. Well done!
History
46
53
A disappointing exam result. He is unable to give attention to this subject for long.
Chemistry
78
85
His obvious ability in the subject was not fully reflected in his exam work, but I have high hopes for him nevertheless.
Physics
86
94
An excellent term’s performance. He goes from strength to strength. A born scientist, I feel.
Biology
57
60
This time next year he will be taking the “0” exam. He needs to concentrate on the work, not on class conversation.
French
41
46
Clearly he didn’t bother to revise. His general attitude is far too casual.
Physical
Education
/
31
Weak. It’s time he exercised his body more and his voice less. He should try to work with a team.
FORM TEACHER’S REMARKS                  HEADMASTER
Basically satisfactory work and progress              I shall be keeping an eye on his
though he will now have realized, I hope, that          progress in his weaker subjects
in certain subject areas he needs to make speedy        though his success in the sciences is
improvement.                                   most pleasing.
小题1:According to the comments of the Physical Education teacher, Simon   .
A．is too talkative in the class
B．likes to work with his classmates
C．doesn’t exercise his body at the right time
D．becomes weak because he doesn’t exercise at all
小题2:Which of Simon’s subjects will attract the headmaster’s attention in future?
A．Biology and Maths. B．History and French.
C．English and Chemistry.D．Physics and Physical Education.
小题3:Which of the following statements best describes Simon?
A．He has made great progress in language classes.
B．His potential has been fully reflected in science classes.
C．His grade in maths makes him a born scientist.
D．He needs to improve his attitude on certain subjects.
小题4: Based on the school report, which of the following statements is true?
A．Simon didn’t bother his teacher to revise French.
B．Basically, Simon did a good job in science.
C．Simon is a determined learner in English.
D．Simon is able to pay attention to history for long.
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