2.Good morning,students.Today we will continue our investigation of the mosquito(蚊子).We all thought that mosquitoes follow skin odors(气味),but no such odor has been identified.It turns out,in fact,that no skin seems to be as attractive to a mo

2.Good morning,students.Today we will continue our investigation of the mosquito(蚊子).We all thought that mosquitoes follow skin odors(气味),but no such odor has been identified.It turns out,in fact,that no skin seems to be as attractive to a mo
2.Good morning,students.Today we will continue our investigation of the mosquito(蚊子).We all thought that mosquitoes follow skin odors(气味),but no such odor has been identified.It turns out,in fact,that no skin seems to be as attractive to a mosquito as a current of air(气流) having the right degree of warmth and humidity(湿度).But,a mosquito can be turned off its course by a repellent(驱蚊剂).This is how it works:a mosquito senses humidity in a airstream by means of tiny pores(气孔) in the hairs located on its antennae(触角).These hairs send electrical impulses to the central nervous system whenever they encounter humidity in the air.The repellent blocks the pores through which mosquitoes sense the presence of water vapor(水汽) in the air.As a mosquito comes in for a landing on a warm moist body,the repellent blocks the mosquito's sensors,and realizing that it has lost its moist current of air,it instinctively changes its course.
1).What is the main topic of this talk?
A.Interaction between mosquitoes and repellents.
B.Components of air currents.
C.Independence of skin odors.
D.The mosquito's central nervous system.
2).According to the speaker,what are mosquitoes attracted to ____?
A.Skin odors
B.Water vapor
C.Warmth and moisture
D.Air currents
3).What does the mosquito repellent do?
A.It changes the moisture in the air.
B.It blocks the hairs in the sensors.
C.It changes the humidity of the skin.
D.It blocks the pores in the hairs.
4).What happens when the mosquito comes into contact with the repellent?
A.It quickly moves off in another direction.
B.Its sensors become blocked by the water vapor in the repellent.
C.The pores in the hairs on its skin become blocked.
D.It sends an electrical impulse to its central nervous system.
5).According to the passage,what can be inferred about mosquito repellents?
A.A degree of instability in their use has emerged.
B.Their reliability has yet to be proved.
C.More research is needed into their efficiency.
D.They appear to be highly effective.

2.Good morning,students.Today we will continue our investigation of the mosquito(蚊子).We all thought that mosquitoes follow skin odors(气味),but no such odor has been identified.It turns out,in fact,that no skin seems to be as attractive to a mo
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2.早安，学生。今天我们将会继续我们的蚊子 （蚊子）的调查。我们全部认为，蚊子跟随皮肤气味 （气味），但是没有如此的气味已经被识别。它事实上出来没有皮肤似乎是当做吸引人的对一只蚊子当做有温暖和湿气 （湿度）的正确程度的空气 （气流）的涌流.但是，一只蚊子能被关掉一个防水剂 （驱蚊剂）的它的课程.这是它如何工作：一只蚊子藉由位于它的天线 （触角）之上的头发的极小毛孔 （气孔）在一个气流中感觉湿气。每...

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2.早安，学生。今天我们将会继续我们的蚊子 （蚊子）的调查。我们全部认为，蚊子跟随皮肤气味 （气味），但是没有如此的气味已经被识别。它事实上出来没有皮肤似乎是当做吸引人的对一只蚊子当做有温暖和湿气 （湿度）的正确程度的空气 （气流）的涌流.但是，一只蚊子能被关掉一个防水剂 （驱蚊剂）的它的课程.这是它如何工作：一只蚊子藉由位于它的天线 （触角）之上的头发的极小毛孔 （气孔）在一个气流中感觉湿气。每当他们在空气中遇到湿气，这些头发将电脉冲送到中央的神经系统。防水剂阻塞毛孔完成的哪些蚊子在空气中感觉水汽 （水汽）的出现。当做一只蚊子在一个温暖的潮湿身体上为登陆进来，防水剂阻塞蚊子感应器，而且了解，它已经遗失它的空气的潮湿涌流，它直觉地改变它的课程。
1)。这一谈话的主要主题是什么？
一。蚊子和防水剂之间的交互作用。
B。空气涌流的成份。
皮肤气味的 C. 独立。
D. 蚊子的中央神经系统。
2)。依照说者，是被吸引到的蚊子＿＿＿＿?
A. 皮肤气味
B. 水汽
C. 温暖和湿气
D. 空气涌流
3)。蚊子防水剂做什么工作？
它在空气中改变湿气的 A.。
它在感应器中阻塞头发的 B.。
C。它改变皮肤的湿气。
D。它在头发中阻塞毛孔。
4)。当蚊子接触到防水剂，发生什么事？
一。它很快地在另外的一个方向中离开。
B。它的感应器变成在防水剂中被水汽阻塞。
C。在它的皮肤上的头发的毛孔变成阻塞。
它将一个电脉冲送到它的中央神经系统的 D.。
5)。依照通道，什么能有关蚊子防水剂被推论出？
一。他们的使用的某一程度的不安定已经出现。
B. 他们的可信度还没有被证明。
C. 更多研究进入他们的效率之内是不可或缺的。
D。他们似乎高度地有效。

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