You Can Make a Windsock (风筒)!

Have you ever seen a windsock blowing in the wind? Well, you can make one of your own!This is a fun project that you can do with things you may have. You just need to follow a few easy steps.

You will need:

●one piece of heavy colored paper ●five ribbons

●strong tape ●a string ●a pencil

What to do:

Step 1:Draw pictures on the paper. You can write your name on it. Do anything that will make it special to you.

Step 2:Make the paper into the shape of a tube. Hold one of the shorter edges over the other. Then make them together with the tape at each end and in the middle.

Step 3:Use a pencil to make a hole into both sides of the tube. The holes should be only on one end of the tube. Pull the string through both holes. Then tie the ends of the string together.

Step 4:Now make five holes around the top of the other end of the tube. Put a ribbon through each of the holes. Tie a knot in the ends. Make sure the knots are bigger than the holes.

Now your windsock is ready to use, but how does it work?The shape of the tube plays an important part. Wind blows through the tube and makes it fly and dance around. Hold the windsock up in the air by its string and run around. It will fly behind you. You can also hang it outside and watch it dance around on its own!

1.Which of these things do you need for Step 2?

A.Tape. B.Ribbons. C.A pencil. D.A string.

2.What do you do after you put ribbons through the holes in the tube?

A.Make holes in the tube. B.Tape the tube together.

C.Tie knots in the ribbons. D.Put a string through the hole.

3.What is probably the most important to make a windsock work?

A.Its shape. B.Its size.

C.The color of the paper. D.The number of the holes.

When a leafy plant is under attack, it doesn’t sit quietly. Back in 1983,two scientists,Jack Schultz and Ian Baldwin,reported that young maple trees getting bitten by insects send out a particular smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be an alarm.What the plants pump through the air is a mixture of chemicals which are called VOCs for short.

Scientists have found that all kinds of plants give out VOCs when being attacked .It’s a plant’s way of crying out.But is anyone listening?Exactly.Because we can watch the neighbours react.

Some plants release smelly chemicals to keep insects away.But others do double duty .They pump out perfumes designed to attract different insects who are natural enemies to the attackers.Once they arrive,the tables are turned .The attacker who was lunching now becomes lunch.

In study after study,it appears that these chemical conversations help the neighbors .The damage is usually more serious on the first plant,but the neighbors ,relatively speaking ,stay safer because they heard the alarm and knew what to do.

Does this mean that plants talk to each other? Scientists don’t know. Maybe the first plant just made a cry of pain or was sending a message to its own branches, and so, in effect, was talking to itself. Perhaps the neighbors just happened to “overhear” the cry. So information was exchanged, but it wasn’t a true communication.

Charles Darwin, over 150 years ago, imagined a world far busier, noisier and more intimate(亲密的) than the world we can see and hear. Our senses are weak. The world is .

1.Does a leafy plant sit quietly when it is under attack?

2.What does a plant do when it is under attack?

3.How can scientists know that there is someone listening to the crying?

4.What does the author mean by “the tables are turned” in paragraphs 3?

5.From the scientists' studies, can plants protect themselves against insects or really talk to each other?

6.What can be filled in the blank at end of the passage?

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