②纳米科技以空前的分辨率为人类揭示了一个可见的原子、分子世界,它的最终目标是直接以原子和分子来构造具有特定功能的产品。人们普遍认为,纳米科技是信息和生命科学技术能够进一步发展的共同基础,将对人类未来产生深远影响。
③从90年代初起,纳米科技得以迅速发展,新名词、新概念不断涌现,如纳米电子学、纳米材料学、纳米机械学、纳米生物学等等。
④科学家为我们勾勒了一幅若干年后的蓝图:纳米电子学将使量子元件代替微电子器件,巨型计算机能装入口袋里;通过纳米化,易碎的陶瓷可以变成韧性的,成为一种重要材料;世界上还将出现1微米以下的机器甚至机器人;纳米技术还能给药物的传输提供新的方式和途径,对基因进行定点等。
⑤正因为如此,世界各国尤其是发达国家都从战略高度部署纳米领域的研究。
1.根据第①段文字,给“纳米科技”下一个定义。
2.从文章看,纳米科技有什么深刻意义?从文中选取有关语句回答。
3.第①段和第④段中加点的“略”“将”能否删去?请分别简要说明理由。
参考答案
1……纳米科技就是以0.1至100纳米这样的尺度为研究对象的前沿学科。
2.纳米科技是信息和生命科学技术能够进一步发展的共同基础,将对人类未来产生深远影响。
3.不能。如果删去“略”,就成了1纳米等于45个原子排列起来的长度;删去“将”,“蓝图”就成了事实,显然与原意不符。
A.电子设备将得到全面更新不再使用电线连接
B.量子棘轮上的电子能在不同电器元件间跳跃
C.只要经过随意分流的电子就能储存量子信息
D.量子棘轮将应用于新一代量子计算机的研制
1。 头绪分明,脉络清楚
写好记叙文,首先要头绪分明,脉络清楚,明确文章要求写什么。要对所写的事件或人物进行分析,弄清事件发生、发展一直到结束的整个过程,然后再收集选取素材。这些素材都应该跟上述五个“ W ”和一个“ H ”有关。尽管不是每篇记叙文里都必须包括这些“ W ”和“ H ”,但动笔之前,围绕五个“ W ”和“ H ”进行构思是必不可少的。
2。 突出中心,详略得当
在文章的框架确定后,对支持故事的素材的选取是很关键的。选材要注意取舍,应该从表现文章主题的需要出发,分清主次,定好详略。要突出重点,详写细述那些能表现文章主题的重要情节,略写粗述那么非关键的次要情节。面面俱到反而使情节罗列化,使人不得要领。这一点是写好记叙文要解决的一个基本问题,也需要一定的技巧。如:
One night a man came to our house and told me, "There is a family with eight children。 They have not eaten for days。" I took some food with me and went。
When I finally came to that family, I saw the faces of those little children disfigured (破坏外貌) by hunger。 There was no sorrow or sadness in their faces, just the deep pain of hunger。
I gave the rice to the mother。 She divided the rice in two, and went out, carrying half the rice。 When she came back, I asked her, "Where did you go?" she gave me this simple answer, "To my neighbors — they are hungry also!"
3。 用活语言,准确生动
记叙文要用具体的事件和生动的语言对人、事、物加以叙述。一篇好的记叙文的语言既要准确、生动,又要表现力强,这样才能把人、事描写得具体生动,其可读性才强。试比较下面一篇例文修改的前后效果。
原文:
One day Xiaoqiang was wandering away。 He was soon lost among people and traffic。 He could not find the way back home and started crying。 Just then, two young students who were passing by found him standing alone in front of a shop and crying。 They went up to Xiaoqiang and asked him what had happened。 Xiaoqiang told them how he got lost and where he lived。 The two students decided to take him home。 Mother was pleased to see Xiaoqiang come back safe and sound。 She invited the two students into the house and gave them some money, but they didn't take it。 She served them with tea but they left。
修改后:
The other day, five-year-old Xiaoqiang left home alone and wandered happily in the street。 After some time, he felt hungry so he wanted to go back home。 But he found he was lost among the crowded people and heavy traffic。 When he could not find the way home, he started and crying。 Just then, two young students who were passing by from school found him sanding crying in front of a shop。 They immediately went up to him。
"Little boy, why are you standing here crying?" they asked。
"I want Mom, I go home。" said the boy, still crying。
"Don't worry, we'll send you home。"
And they spent the next two hours looking for the boy's house。 With the help of a policeman, they finally found it。
When the worried mother saw her son come back safe and sound, she was so thankful and she invited the students into her house。 Gratefully, she offered them some money, saying it was a way to express her thanks, but the young students firmly refused it and left without even a cup of tea。
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