Most of the flowers in nature are red, orange and yellow. If we have seen a black flower, it’s a chance in a million.
People have made a census (普查) to colors of mor e than four thousand kinds of flowers and discovered that only eight of them are black.
As we know, sunlight is formed by seven different colored lights.The wave length of each light is different, so the quantity of heat in each light is also different. Flowers, especially their petals, are easy to be harmed by light temperature.
Black flowers can take in all the light waves which cause the flowers to dry up in the high temperature. So black flowers can rarely survive sunlight. But red flowers, yellow flowers and orange flowers can protect themselves from sunlight by reflecting the red light, yellow light and orange light, each of which has a large quantity of heat.
1. It is _____ to see a black flower.
A. impossible     B. seldom          C. common       D. no chance
2. From the passage we know that _______.
A. black flowers are so weak that it is difficult for them to grow up.
B. there are only eight black flowers in nature
C. sunlight is formed by seven different colored lights, so the wave length of each light is different
D. black flowers can take in the light of all the wave length which makes them dry up because of high temperature
3. Which of the following ideas is WRONG?
A. People have found that only a few kinds of flowers are black.
B. Flowers are easy to be harmed by very high temperature.
C. Red, orange and yellow flowers can also take in the light of all wave lengths.
D. The black flowers can’t protect themselves from sunlight.