Besides providing a perfect environment for sea plants and animals to live in, seawater has other values, one of which is that it constantly moves, and its movements produce energy.
The most obvious movements are the waves and the tides. Winds cause the waves, and the gravitational pull of the moon and the sun causes the tides. In places like the Bay of Fundy in Canada, the difference between the high and low tide level can be as much as 40 feet.
France and Britain are now trying to use energy in the tides to produce electricity. Waves can produce electricity and some experiments are taking place to learn more about this. One of the most encouraging areas of research uses the difference between the temperature of seawater at the surface and deep down to produce electricity. 
【小题1】Waves and tides are caused by ________ .

第三部分阅读理解 (共15小题；每小题2分，满分30分)
请认真阅读下列短文，从短文后各题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。
When the first spring flowers blossom, Easter comes. It is the oldest Christian feast, in memory of the resurrection (复活) of Jesus Christ.
Along with the traditional Easter walk or outing, the giving of Easter eggs and, more recently, of Easter presents is a main feature of the feast. Parents give their children “Easter eggs” – colored and boiled eggs, chocolate eggs, marzipan eggs – Easter bunnies, sweets, and other gifts. In some German regions, children virtually “collect” Easter eggs from their relatives, especially their godparents.
Usually, the Easter eggs are carefully hidden in the garden or in the house and the children must search for them on the morning of the Sunday. They are told that the Easter bunny has brought them. This anonymous, mysterious bunny is like Santa Claus at Christmas. But it is less of an “educational” figure than Santa Claus is, since the eggs are not given to children as rewards for being good.
Some Easter egg games have been preserved at certain places in Germany or have even been newly developed. Children try to outdo others in rolling colored eggs down grassy slopes, for instance, or they knock the eggs’ pointed ends together and the child whose egg does not shatter gets the broken one, too. In some places, this custom was even used as the name of local festival.
1.What are the main features of Easter?
A.Easter walk, Easter eggs, Easter bunnies and sweets.
B.Easter outing and the giving of Easter presents.
C.Easter walk, Easter eggs, Easter bunnies and Easter egg games.
D.Easter outing, the collecting of Easter eggs, and Easter games
2.The underlined word “outdo” means ________.
A. do better than           B. do worse than           C. do slower than          D. do the same as
3.What can be inferred from the passage?
A.Easter bunny will give gifts to children for better or worse.
B.Easter bunny is very similar to Santa Claus, as they both bring gifts to children.
C.Easter always falls on a Sunday.
D.Some of the local festivals are named by Easter egg games.

Here in Alaska, the wolf almost disappeared a few years ago, because hunters were killing hundreds of them for sport. However, laws were passed to protect the wolves from sportsmen and people who catch the animals for their fur. So the wolf population has greatly increased. Now there are so many wolves that they are destroying their own food supply.
A wolf naturally lives on animals in the deer family. People there also hunt deer for food. Many of the animals have been destroyed by the very cold winters recently and by changes in the plant life there. When the deer can’t find enough food, they die.
If the wolves continue to kill large numbers of deer, the deer will disappear some day. And the wolves will, too. So we must change the life cycles there. If we killed more wolves, we would save them from starving. We also save deer and some farm animals.
In another northern state, wolves attack cows and chickens for food. Farmers want the United States government to send a team of scientists to study the problem. They believe it is necessary to kill wolves in some areas and to protect them in places where there is a small population.
【小题1】In Alaska, laws have been passed to ____.