If we are driving a car or crossing a street, we will stop when the traffic lights turn red．Why do we use red rather than other colors?
As we know, scattering(散射)happens when light goes through the air．For the same media, if the wavelength(波长)is long, the scattering will be short．If the wavelength is short, then the scattering will be long．
Of all light we can see red has the longest wavelength, so the scattering is the weakest．That means the red light travels far．In fact, it travels farther on rainy days．
Using the red light can help drivers in farther areas see the lights．It helps drivers slow down or stop in time．If drivers don’t see the red light until they are close, they may not be able to stop the car in time．An accident may happen．Red can also excite people．We can act more quickly when we see the color red．
In a word, red light helps drivers stop in time and helpprevent accidents．
(1)
_________ has the longest wavelength of all light we can see．
[ ]
A．
Red
B．
Green
C．
Yellow
D．
Black
(2)
Red light travels farther on _________ days．
[ ]
A．
windy
B．
sunny
C．
rainy
D．
cloudy
(3)
Red can make people act more quickly because _________．
[ ]
A．
red can make people happier
B．
the scattering of red is very short
C．
the scattering of red is very long
D．
red can make people more excited
(4)
The underlined word “prevent” means _________ in Chinese．
We have three kinds of pizzas，small，medium and large．A small pizza with pepperoni．onions and olives is \$ 3.5．A medium pizza with mushrooms． tomatoes and cheese is \$ 4．0．A large pizza with olives and cheese is \$4．7．
Welcome to our house!
Lunch Special
We have some great specials．The pizza with cheese and tomatoes is just \$2．50．The cheap for \$1．50 has green peppers and onions．The pizza and salad lunch special is \$ 2．90．
Time：11：00 a．m．～2：00 P．m．
Pizza Express
Tel：825-3933
The Californian pizza with mushrooms，olives and green peppers is just \$3．00．The pizza with pepperoni and olives is \$ 2.50．The hot dog is \$ 1．50． The lemonade is \$ 1．00．The juice is \$ 0．5．
Order a meal today!
(1)
If you want to buy a small pizza，a medium pizza and a large pizza, you can pay _____ .
A．\$12．20 B．\$8．20 C．\$8．70 D．\$12．70
[ ]
(2)
If you go to the House of Pizza，you can buy 3 medium pizza with _____ on it．
A．pepperoni,onions and olives
B．olives and cheese
C．green peppers and onions
D．mushrooms，tomatoes and cheese
[ ]
(3)
If you only have \$1．50 with you，you can buy _____ at lunch time．
A．a pizza with green peppers and onions on it
B．a pizza with cheese and tomatoes on it
C．the pizza and salad lunch
D．a pizza with pepperoni and cheese
[ ]
(4)
If you want to order a pizza，you can _____ ．
A．go to the House of Pizza B．get a lunch special
C．call 825-3933 D．go to the Pizza Express
[ ]
(5)
In the House of Pizza，you can buy _____ ．
A．lemonade B．juice C．iced tea D．a large pizza
[ ]
阅读理解
Most American children eat potatoes．But many children don't know what of the potato is the best for food．Take a knife and cut from the middle of the potato a piece as thin as paper．Hold the piece between your eyes and light．You will see that the potato has skin(皮)，an outside rim(边缘) and an inside part．The outside rim which is right under the skin of the potato，is the most valuable part of all．But this is often thrown away with the skin．Even the skin itself is better for food than the inside．When eating a cooked potato，if you choose the inside and leave the outside，you are throwing the best part of it．If you can't eat the whole potato，eating the outside rim and leaving the inside will do．
(1)
How many parts does the potato have?
A．It has only one part，outside rim．
B．It has two parts，skin and outside rim．
C．It has three parts，skin，outside rim and an inside part．
D．It has four parts，middle，skin，outside rim and an inside part．
[ ]
(2)
What is the best part of a potato?
A．Outside rim． B．Inside part． C．Middle． D．Skin．
[ ]
(3)
What should you eat first if you can't eat the whole potato?
A．Skin only． B．Inside． C．Outside rim． D．Part of it．
[ ]
(4)
In fact the skin is ______．
A．no good at all
B．better than the inside part
C．better than the outside rim
D．as good as the outside rim
[ ]
(5)
What does this passage tell about potatoes?
A．How to cook them．
B．How to plant them．
C．What is made up of a potato．
D．How to eat them．
[ ]
阅读理解
You will have a lot of reading to do in this grade this year．You can do more of it in less time if you learn to read rapidly．
Perhaps you have been told about some habits (习惯) which keep a person from reading fast and have been strongly asked to break those habits which you might have．
Do you still have any of these bad habits?Check yourself by answering“yes”or“no”to these questions．
(1) Do you move your lips (嘴唇) when reading silently?
(2) Do you point to words with your finger as you read?
(3)Do you move your head from side to side as you read?
(4)Do you read one word at a time?
If you answer“yes”to any of these questions,start at once to break the habit．If you move your tips，hold your fingers over them，or hold a piece of paper be-tween your lips while you are reading．Then if your lips move，your will know it and can stop them．
If you point to words，hold the two sides of your book，one side with your left hand，the other side with your right hand．Then you won't have a free finger to use in pointing while reading．If you move your head，place your chin (下巴) in one hand and hold your head still (静止不动的)．
If you read no more than one or two or three words at a time，you need to work very hard in learning to take in (吸收) more words at each glance (一瞥) as your eyes travel across the lines of words．
Even if you do rather fast now，you can learn to read even faster．As you probably have been told，the secret of fast reading is to take in whole groups of words as each glance．Read in through groups and force (迫使) your eyes along the lines of words as fast as you can to make them go．Anyone who practices doing these things will he able to read faster．
(1)
You may hold your fingers over your lips while reading so as ______．
A．to tell others to be silent
B．to feel whether your lips move or not
C．to hold a piece of paper between them
D．to keep yourself from talking to others
[ ]
(2)
When you read，______．
A．don't keep your head still
B．don't hold your books with your hands
C．don't stand up near a desk
D．don't use your finger to point to words
[ ]
(3)
If you learn to read fast，______．
A．you can read more in less time
B．you can write faster
C．you can understand better
D．you can read less in more time
[ ]
(4)
You must _______ those habits that we are talking about in this reading．
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