Yellow, orange, red and green- tree leaves make autumn a colourful time! Who paints all these colours? It is the leaves themselves. Inside a leaf, there are millions of little colour“bags”, they are green, yellow and orange. The green ones are called chlorophyll（叶绿素）.The yellow ones are called xanthophylls（叶黄素）. The orange ones are called carotene（胡萝卜素）.

　　In summer, the green chlorophyll is very, very busy. It makes food for the trees. It catches sunlight to change water and carbon dioxide（二氧化碳）into sugar. This sugar is the food for ther tree. It is so busy that it covers up all of the other colours in the leaf.

　　When the weather grows colder in autumn, there is less light and water for trees. The trees will have a rest to get ready for winter. They've made enough food in summer! The leaves no longer need water to make food. Without the water, the green chlorophyll starts to go away. The other colours in the leaf-the yellow xanthophylls and orange carotene come out. So the leaves don't really“turn”a certain colour. They just lose their green !

　　The leaves look red or purple because they have some sugar in them. They“steal”some food from the tree! The green leaves are from the evergreen trees （常绿树）. The evergreen trees stay green all year long. Their leaves don't lose water in winter.

(1) The tree leaves have the following colour“bags”, such as green, yellow and orange except red.

(2) In summer, the green chlorophyll works hard for the tree leaves.

(3) In autumn, the tree leaves turn yellow or orange because the green chlorophyll stops working and goes away.

(4) Tree leaves no longer make food in summer.

(5) We can infer（推断）from the article that trees can clean the air.

阅读填词

　　Algae are plants that have no roots or leaves. They grow in w 1 place. You may have seen algae on top of the water in a pond or l 2 . Most algae are green or blue, but some are red, b 3 or black. Often you buy algae at the store, but you don't know it. Some k 4 of algae are used in making ice cream, tooth paste, skin creams, and medicine.

　　Algae don't look or taste good, but they are h 5 in food value. They can be made into flour. Women and men are working to make algae taste b 6 . Then they can be used for food. Tomorrow, m 7 people will live in the world. They will n 8 more food to eat.

　　Algae are e 9 to grow. They may become an important f 10 .

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6．b　　　7．m　　　8．n　　　9．　　　10．f　　

缺词填空 根据短文内容及首字母提示，补全空格内单词，使短文完整、通顺（共10空；每空1分，满分10分）

Last May I stayed in Santo Lusa for a week. That was my f  1  trip there. One morning I went out to v  2   a famous museum but l didn't know w   3  way to go,  so l stopped a stranger and asked “ Excuse me, does this street lead(通向) to the Grand Museum?”“Yes,” he answered. “Go along this street and turn left at the second crossing. You can't m  4　it. ”so I walked two blocks (街区) and t   5  to my left，but the museum w   6   there. Then I asked a second stranger. He said,“Go along this street and turn left at the second crossing.” But a  7　I couldn’t find the museum. I asked a third stranger and he said the same thing. This time I found the Grand Museum. Just then s  8  walked up and said, “ Excuse me, where’s the nearest h  9  ? I have a bad headache. ” I answered q 10  “ Go along this street and turn left at the second crossing !”

1.f________  2. v________  3. w________  4. m________  5. t________

6.w________  7. a________  8. s________  9. h________  10. q_______