问题补充：
What do you do if you e in trouble on a lonely island? Surely you need to find a way to get in touch with the outside world. Your best chance of doing this is to draw the attention of a passing plane.
Body signals (信号)
Pilots from different countries understand body signals if they have the correct training, When you wave your arms up and down in a straight line, it means, yes. When you point downwards and swing your arm from side to side, it means no. If you want the pilot to know that its safe to land, push your hands out in front of you and bend (弯曲) your knees. If you want to say that its not safe to land, put your arms in the air and move them to one side.
Smoke signals
The smoke from a fire can be seen from far away, so it’s a good way to draw attention. If the weather is dry, it isn’t hard to start a fire. Remember, however, that fires can be very dangerous if they get out of control. Never light a tire unless you e sure that it can’t spread. If the ground is dark, light smoke can be seen more easily. Green grass and leaves produce light smoke.
Ground-to-air signals
Its a good idea lo build some signals, too. Use large pieces of wood to make the symbols (标记). If you can find any wood, use earth. Some useful symbols are:
F I need food and water
II I need medicine.
I I am badly hurt.
X I am unable lo move from here.
Pilots replies
If the pilot lowers the planes wings from side to side, this means: message received and understood (At night, the pilot flashes the planes green lights.) If the pilot flies the plane in a clockwise circle, this means message received hut not understood (At night, the: pilot flashes the plants red lights.)
However, there is no signal which means message not received. Why not?
【小题1】How many signals can we use to draw the attention of the passing plane if you e in trouble?A．Three.B．FourC．FiveD．Six【小题2】Which picture means its not safe to land?
【小题3】What can we learn from the passage?
A. Swinging your arm from side to side means yes
B. If the ground is dark, light smoke can’t be seen.
C If you need some medicine, make a symbol “Ⅱ”.
D. The pilots make replies with a blue light at night.
【小题4】What is the passage mainly about?A．The explanation of building signals on an island.B．The importance of making signals on an island.C．Ways of sending out signals on a lonely island.D．Ways of receiving signals from a lonely island.A
答案：
(答案→)A
解析：
【小题1】根据文章内容可知答案为A
【小题2】根据文章内容可知答案为D
【小题3】根据文章内容大意可知答案为C
【小题4】从文章内容可知答案为C
