如图，△ABC中，AB⊥BC，AD⊥BD，CE⊥BD，AB=BC，若CE=6，AD=2，求DE的长

如图，△ABC中，AB⊥BC，AD⊥BD，CE⊥BD，AB=BC，若CE=6，AD=2，求DE的长

Comets(彗星) are parts of our solar system. Like the planets, they go around the sun.
But comets are not made of solid rocks like planets. A comet is a ball of dust, stones, and ice. Many people call comets dirty snowballs.
The "snowball"may be only a few miles across. But when the sun heats the "snowball,"much of it is changed to gases. The gases spread out and form the comet's head, which may be thousands of miles across.
A comet moves fast in its trip around the sun. But when we see it, the comet does not seem to move. That's because it is so far away. The moon moves fast, but when you look at it, you can't see any motion(运动). That's because the moon is far away.
Each year astronomers(天文学家) discover new comets. Some of them are seen only once. They make one trip around the sun and then go away out into space. The sun's gravity cannot hold them.
Other comets, like Halley, keep returning. They have been captured by the sun. Halley's earliest visit was probably 3,000 years ago. It may keep returning for another 3,000 years.
But every time a comet goes around the sun, the comet loses part of itself. Gases and dust are pulled out of the comet. That's why Halley is now dimmer（暗淡的） than it used to be. Next time it visits us, in 2062, it may be even dimmer. Each visit it may get dimmer and dimmer, until it finally disappears.

阅读下文，回答相关问题

                                                                                                            课内阅读
        有一年的春天，我因病被迫在家里休息数周。我注视着我的女儿们所养的蚕正在结茧，这使我感兴趣。望着这些蚕执著地、勤奋地工作，我感到我和它们非常相似。像它们一样，我总是耐心地把自己的努力集中在一个目标上。我之所以如此，或许是因为有某种力量在鞭策着我，正如蚕被鞭策着去结茧一般。
        近五十年来，我致力于科学研究，而研究，就是对真理的探讨。我有许多美好快乐的记忆。少女时期我在巴黎大学，孤独地过着求学的岁月；在后来献身科学的整个时期，我丈夫和我专心致志，像在梦幻中一般，坐在简陋的书房里艰辛地研究，后来我们就在那里发现了镭 。

        我永远追求安静的工作和简单的家庭生活。为了实现这个理想，我竭力保持宁静的环境，以免受人事的干扰和盛名的拖累。
        我深信，在科学方面我们有对事业而不是对财富的兴趣。当皮埃尔·居里和我考虑要不要在我们的发现上取得经济利益时，我们都认为不能违背我们纯粹研究的观念。因而我们没有申请镭的专利，也就抛弃了一笔财富。我坚信我们是对的。诚然，人类需要讲究现实的人，他们在工作中获得很多的报酬。但是，人类也需要梦想家，他们受事业的强烈的吸引，既没有闲暇也没有热情去谋求物质上的利益。我的惟一奢望是在一个自由国家中，以一个自由学者的身份从事研究工作。我从没有把这种权益视为理所当然，因为在二十四岁以前，我一直居住在被占领和被蹂躏的波兰。我估量过在法国得到自由的代价。

Father's Day has a very short history. It was started because there was a Mother's Day, and just because some Americans thought that if we had a Mother's Day, we should also have a Father's Day. Father's Day has become important in North America. And businesses found it was a good way to get people to buy a present for their father from their shops.
By the way, very few countries have a Father's Day, though some have a Children's Day, or a special day for boys and another for girls. More and more countries are having Mother's Day, so maybe Father's Day will also become popular before too long. Now, what do people in North America do on Father's Day? The newspapers, radios, and TV tell children what they should do — buy, buy, buy, buy, buy a Father's Day present for your father. They even tell a wife to buy, buy, buy, and buy a Father's Day present — not for her father but for her husband, even if he is not yet a father. And they tell grandchildren to buy, buy, buy, and buy a Father's Day present for their grandfathers.
The important thing to remember about Father's Day is that American children can show their love to their fathers in a more open way.

   Many people don’t think that the number 13 is a lucky number. Many hotels do not have a 13th floor. The floors go from 12 to 14, and there is no number13. Some people will never sit at a table with 12 other people. They will tell someone to go or ask another person to sit with them.
No one really knows why people do not like the number 13. Perhaps one reason is that when people began to count, they used ten fingers and two hands. This made 12. They could not count more.
   Some Christians (基督徒) say that 13 is not lucky because there were 13 people at a meal the day before Jesus (耶稣) was killed (被杀). In a story about the old Greek (希腊的) gods, 12 gods were asked to a meal but one more came. This made 13. It is why the god Balder, who was at the meal, was killed.

   Many people don’t think that the number 13 is a lucky number. Many hotels do not have a 13th floor. The floors go from 12 to 14, and there is no number13. Some people will never sit at a table with 12 other people. They will tell someone to go or ask another person to sit with them.
No one really knows why people do not like the number 13. Perhaps one reason is that when people began to count, they used ten fingers and two hands. This made 12. They could not count more.
   Some Christians (基督徒) say that 13 is not lucky because there were 13 people at a meal the day before Jesus (耶稣) was killed (被杀). In a story about the old Greek (希腊的) gods, 12 gods were asked to a meal but one more came. This made 13. It is why the god Balder, who was at the meal, was killed.

Having Fun "Growing" and "Stealing"？
Recently, an Internet game has become a new fashion among young office workers and students．People can "farm" on a piece of "land" and "grow", "sell" or even "steal" "vegetables", "flowers" and "fruits" on the Net. They can earn some e-money and buy more "seeds", "pets" and even"houses".
Joyce interviewed some young people. Here are their opinions．
Harold：I don't quite understand why they are so mad about the childish game; maybe they are just not confident enough to face the real world.
Allan：I enjoy putting some "bugs" in my friends' gardens and we've become closer because of the game．Having fun together is the most exciting thing about it．
Laura：You know, people in the city are longing for(渴望) the life in the countryside．It reduces my work pressure(压力)；besides, it gives me the exciting experience of being a "thief"．
Ivy：  Well. it's just a waste of time．Teenagers playing the game spend so many hours on it that they can not focus on (专注于)their study.

根据所给的汉语，用英语完成下列句子
你想住在一个繁华街道上的饭店隔壁吗？
Would you like to live{#blank#}1{#/blank#}  a restaurant on a busy street?
Tony经常迫不及待地跑回家在电视上看球赛。
Tony often  {#blank#}2{#/blank#}  run home and watch football matches on TV.
那位老人总是朝窗外看街上的孩子们。
The old man often{#blank#}3{#/blank#} the window at the children in the street..
那个穿着一件红色衬衫的人是我们的英语老师。
The man {#blank#}4{#/blank#} shirt is our English teacher.
我们可以在运动用品商店找到适合他的东西。
We can {#blank#}5{#/blank#}  for him in a sports shop.

根据所给的汉语，用英语完成下列句子
你想住在一个繁华街道上的饭店隔壁吗？
Would you like to live{#blank#}1{#/blank#}  a restaurant on a busy street?
Tony经常迫不及待地跑回家在电视上看球赛。
Tony often  {#blank#}2{#/blank#}  run home and watch football matches on TV.
那位老人总是朝窗外看街上的孩子们。
The old man often{#blank#}3{#/blank#} the window at the children in the street..
那个穿着一件红色衬衫的人是我们的英语老师。
The man {#blank#}4{#/blank#} shirt is our English teacher.
我们可以在运动用品商店找到适合他的东西。
We can {#blank#}5{#/blank#}  for him in a sports shop.

The {#blank#}1{#/blank#}  (首都) of the USA is Washington DC.
The little girl often{#blank#}2{#/blank#}  (哭) when her mother leaves.
There are twenty students in his class. He always comes the {#blank#}3{#/blank#}  (二十).
The young like to wear trainers, because they are very{#blank#}4{#/blank#} (舒适).
{#blank#}5{#/blank#} (最后), we all get to the top of the hill.
Tom’s shoes are the same as those{#blank#}6{#/blank#}  (cook) in the food shop.
There are some {#blank#}7{#/blank#}  (shelf) over there. On them are some books.
Girls like to wear{#blank#}8{#/blank#}  (colour) dresses.
That’s too expensive. Do you have a{#blank#}9{#/blank#}  (cheap) pair?
Simon is {#blank#}10{#/blank#} (lie) on his bed. He’s listening to the pop music.