What is color? Why do some of the things around us look red, some green, others blue?
Colors are really made by reflected(反射)light. We see color because most of the things reflect light. Something is red, for it reflects most of the red light. In the same way, if something is green, it reflects most of the green light. If something reflects all light, it is white. If it doesn’t reflect any light, it is black.
Some of the light is reflected and some is taken in (吸引)and turned into heat. The darker the color is, the less light is reflected, the more light is taken in. So dark-colored clothes are warmer in the sun than light-colored clothes.
根据短文内容，判断正(T)误(F)
1.When something reflects light, we can see its color.
2.Something looks white because it reflects all light.
3.The dark-colored clothes are warm because less light is taken in.
4.In summer light-colored clothes make people feel cool.
5.Color is the best title of this passage.
People all over the world eat rice.___people, in Asia(亚洲), Africa(非洲)and South America___it every day of their lives. Some people almost do not eat___except rice.
Rice is a kind of____ There are more than 7000 kinds of rice. Most kinds are water plants. Farmers___rice in many countries even in the southern part of Russia and in eastern Australia.
No one really knows where rice___. Someone in China wrote about it almost 5000 years ago. Some scientists think that rice___in West Africa,___think it___from India and then ___to other parts of the world.
1.A. Thousands of B. Hundreds of C. Millions of D. A million of
2.A. eat B. eats C. eaten D. is eaten
3.A. everything B. something C. anything D. nothing
4.A. grass B. fruit C. flower D. vegetable
5.A. make B. run C. keep D. grow
6.A. came from B. came to C. went from D. went to
7.A. grew B. grow C. is grown D. was grown
8.A. another B. other C. the other D. others
9.A. came B. come C. was come D. was coming
10.A. was planted B. was taken C. was kept D. was grown
The number of students in our class ____ 50. And a number of students _____ planting trees now.
A. are, are B. is, is C. are, is D. is, are
____ said that some foreigners will come to our school.
A. They are B. They is C. That is D. It is
Nothing can stop such a thing from _____ again.
A. happen B. to happen C. happening D. happed
She has taken my book ___.
A. by mistaken B. by mistake C. for wrong D. make a mistake
