题目内容
In the sea there are many islands（ 岛 ）. In its warm waters there are some little ones. We call them “coral islands（珊瑚岛）”. A coral island is very nice to look at. It looks like a ring of land with trees, grass, and flowers on it. One part of the ring is open to the water.
There is a little round lake inside the island. If you look into the lake, you will see beautiful corals. You may think they are flowers.
If you look at a piece of coral, you will see many little holes（洞）in it. In each of these holes a very small animal has lived. These sea animals make the coral.
They begin to build coral under the water year after year, the coral grows higher and higher. At last it grows out of water.
Then the sea brings it to small trees or something else. After some years, these things change into earth. Sometimes the wind brings seeds（ 种 子 ）to the earth. Sometimes birds fly over it and bring seeds to the island.
The little seeds grow. In a few years there are plants all over the island. In a few more years there are trees growing there.
So you see, the islands are built little by little（渐渐地）. The workers are very small. Don’t they teach us a lesson?
1.________looks like a ring of land.
A.The sea B.The coral island C.The water D.The tree
2.Inside the island there is a________.
A.lake B.river C.hill D.land
3.________look like flowers in the lake.
A.The fish B.The islands C.The corals D.The birds
4.The sea animals begin to build________under the water.
A.flowers B.coral C.trees D.grass
5.________doesn’t bring small trees or seeds to the island.
A.The sea B.The wind C.The snow D.The bird
