What do you do if you're stranded（处于困境的）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 it's safe to land, push your hands out in front of you and bend（弯曲）your knees. If you want to say that it's 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 fire unless you're 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
　　It's a good idea to build some signals, too. Use large pieces of wood to make the symbols(标记). If you can't 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 to move from here."
　　Pilots' replies
　　If the pilot lowers the plane's wings from side to side, this means "message received and understood". (At night, the pilot flashes the plane's green lights.) If the pilots flies the plane in a clockwise circle, this means "message received but not understood".(At night, the pilot flashes the plane's red lights.)
However, there is no signal which means "message not received". Why not?
【小题1】 Which picture means "it's not safe land"?

　
【小题2】 What can we learn from the passage?

What do you do if you're 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 it's safe to land, push your hands out in front of you and bend (弯曲) your knees. If you want to say that it's 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're 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
It's a good idea lo build some signals, too. Use large pieces of wood to make the symbols (标记). If you can't 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 plane's wings from side to side, this means: "message received and understood" (At night, the pilot flashes the plane's 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're in trouble?

Do your kids ask a lot of questions? If they do, that’s great. Because that’s how children learn. Some of these questions may be easy to answer. Others may be hard. And they want to get the right answers. Do your kids ask such questions?
●Why is the sky blue? Why is the sunset red?
●Why are leaves green?
●Why do leaves change color in autumn?
●How do airplanes fly?
Can you answer these questions? If not, don’t worry. Though Science Made Simple can’t help with all of life’s important questions, it can help with those. In this fast changing world, the more your children know about science, the better.
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【小题1】What do we know about the kids who like asking questions?