题干

设全集U=R.若集合A={1,2,3,4},B={x|2≤x≤3} ,则ACuB=____ .
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{1,4}

同类题1

阅读理解

    I look around and can't recognize where I am. It seems familiar but distant. I see my friends gather by a stage where music is playing and I run over. As I begin running towards them, they become further and further away. I keep calling them, but no one hears me. I start hearing a distant alarm-like sound and I am transported away. I woke up in a daze sitting in my bed.

    “Oh, it was only a dream,” I said to myself. I have always had vivid and intense dreams. It feels like I haven't even slept because I have been living out my dreams during my sleep.

    Today, dreaming is being studied even more than ever. Some say that dreams are how your receptors make sense of random thoughts while you sleep. Some say that you can't dream of a face you have never seen before, so everyone you see in your dreams you have at least laid eyes on at one time or another.

    Other people think dreams are ways of expressing stress or internal feelings you may be experiencing. A lot of people say that they have dreams about being chased.

    A common interpretation of the “being chased” dream is that you are feeling threatened. Some dream interpretation websites say you should try to reflect on what or who is chasing you to get a better idea of what is making you feel this way.

    Another dream that is often experienced is flying. This dream has a much more positive interpretation, which is that you are feeling free or have broken out of a bad situation such as a relationship turned sour or a job you hate.

Unfortunately, you may forget half of your dream within five minutes of waking up and within 10 minutes, you usually forget 90 percent of it.

    Dreamologists, people who devote time to the study and interpretation of dreams, suggest if you want to try to remember and study your dreams you should keep a journal beside your bed and write down what you dreamt as soon as you wake up so you can reflect on it later.

同类题3

阅读下面的文字,完成小题。

(一)优哉游哉

伯尔

在欧洲西海岸的一个码头,一个衣着寒伧的人躺在他的渔船里闭目养神。

一位穿得很时髦的游客迅速把一卷新的彩色胶卷装进照相机,准备拍下面前这美妙的景色:蔚蓝的天空、碧绿的大海、雪白的浪花、黑色的鱼艇、红色的渔帽。咔嚓!再来一下,咔嚓!德国人有句俗语:好事成三。为保险起见,再来个第三下,咔嚓!这清脆但又扰人的声响,把正在闭目养神的渔夫吵醒了。他睡眼惺忪地直起身来,开始找他的烟盒。还没等找到,热情的游客已经把一盒烟递到他跟前,虽说没插到他嘴里,但已放到了他的手上。咔嚓!这第四下“咔嚓”是打火机的响声。于是,殷勤的客套也就结束 了。这过分的客套带来了一种尴尬的局面。游客操着一口本地话,想与渔夫攀谈攀谈来缓和一下气氛。

“您今天准能捕到不少鱼吧?”

渔夫摇摇头。

“不过,听说今天的天气对捕鱼很有利。”

渔夫点点头。

游客激动起来了。显然,他很关注这个衣着寒伧的人的境况,对渔夫错失良机很是惋惜。

“哦,您身体不舒服?”

渔夫终于从只是点头和摇头到开腔说话了。“我的身体挺好,”他说,“我从来没感到这么好。”他站起来,伸展了一下四肢,仿佛要显示一下自己的体魄是多么的强健。“我感到自己好极了!”

游客的表情显得愈加困惑了,他再也按捺不住心中的疑问,这疑问简直要使他的心都炸开了:

“那么,您为什么不出海呢?”

回答是干脆的:“早上我已经出过海了。”

“捕的鱼多吗?”

“不少,所以也就用不着再出海了。我的鱼篓里已经装了四只龙虾,还捕到差不多两打鲭鱼……”渔夫总算彻底打消了睡意,气氛也随之变得融洽了些。他安慰似的拍拍游客的肩膀,在他看来,游客的担忧虽说多余,却是深切的。

“这些鱼,就是明天和后天也够我吃了。”为了使游客的心情轻松些,他又说:“抽一支我的烟吧?”

“好,谢谢。”

他们把烟放在嘴里,又响起了第五下“咔嚓”。游客摇着头,坐在船帮上。他放下手中的照相机,好腾出两只手来加强他的语气。

“当然,我并不想多管闲事,”他说,“但是,试想一下,要是您今天第二次、第三次,甚至第四出海,那您就会捕到三打、四打、五打,甚至十打的鲭鱼。您不妨想想看。”

渔夫点点头。

“要是您,”游客接着说,“要是您不光今天,而且明天,后天,对了,每逢好天都两次、三次,甚至四次出海——您知道那会怎么样?”

渔夫摇摇头。

“顶多一年,您就能买到一台发动机,两年内就可以再买一条船,用这两条船或者这条机动渔船您也就能捕到更多的鱼——有朝一日,您将会有两条机动渔船,您将会……”他兴奋得好一会儿说不出话来。“您将可以建一座小小的冷藏库,或者一座熏鱼厂,过一段时间再建一座海鱼腌制厂 。您将驾驶着自己的直升飞机在空中盘旋,寻找更多的鱼群,并用无线电指挥您的机动渔船,到别人不能去的地方捕鱼。您还可以开一间鱼餐馆,用不着经过中间商就把龙虾出口到巴黎。然后……”兴奋又一次哽住了这位游客的喉咙。他摇着头,满心的惋惜把假期的愉快一扫而光。他望着那徐徐而来的海潮和水中欢跳的小鱼。“然后——”他说,但是,激动再一次使他的话噎住了。

渔夫拍着游客的脊背,就像拍着一个卡住了嗓子的孩子。“然后又怎样呢?”他轻声问道。

“然后,”游客定了一下神,“然后,您就可以优哉游哉地坐在码头上,在阳光下闭目养神,再不就眺望那浩瀚的大海。”

“可是,现在我已经这样做了,”渔夫说,“我本来就优哉游哉地在码头上闭目养神,只是您的‘咔嚓’声打扰了我。”

显然,这位游客受到了启发,若有所思地离开了。此时,在他心里,对这个衣着寒伧的渔夫已没有半点的同情,有的只是一点儿嫉妒了