Would与Used to的表意异同

现代英语中,used to结构属于情态助动词范畴,常被用来表达过去的某种习惯性的或重复性的动作,其语法意义与情态动词would有异曲同工之处;两者均可与动作动词搭配,表示过去的习惯,但现在这种习惯已不复存在。句式结构中常含有明显的与现在对照的意思。例如: 〈1〉Our postman used to knock loudly on our door;now he merely slips the letters through the let-     

过去完成时的几种特别用法

引言:一般语法书上说过去完成时的动作发生在“过去的过去”,也就是说过去完成时的动作须在过去某一时间以前完成。如;We arrived to find that the train had left two minutes be-fore.我们到达车站时发现火车在两分钟前开走了。(火车离站先于我们到达车站的时间。)所以主句动词用的是arrive的过去一般时形式arrived,而从句动词则用的是leave的过去完成时形式had left。那么是否所有的过去完成时行为一定都发生在过去一般时之前?本文试图在此方面作些探讨。     

求sum from k=1 to n K~m的另一种递推方法

对于自然数方幂和 sum from k=1 to n K~m (m、n 为自然数),可将其展为关于 n 的一个(m 1) 次多项式,该问题有关杂志曾刊载过文章,介绍了几种推证方法。本文用与过去的讨论完全不同的初等方法探讨了此问题,得出了求解多项式系数的递推公式。从而得出 sum from k=1 to n K~m 的计算公式。     

在化学教学中运用SATL--埃及的一种新型教学方法

过去几年中,在埃及的科学教育中心的积极倡导下,该国的各级教育部门卓有成效地推行了一种很有创新精神的教学方法--系统教学法(Systemic Approach to Teaching and Learning,简称SATL).本文先介绍系统教学法的基本思路,然后以烷烃化合物教学为例,阐述了该法的优越性.     

在化学教学中运用SATL——埃及的一种新型教学方法

过去几年中，在埃及的科学教育中心的积极倡导下，该国的各级教育部门卓有成效地推行了一种很有创新精神的教学方法——系统教学法(Systemic Approach to Teaching and Learning,简称SATL)．本文先介绍系统教学法的基本思路，然后以烷烃化合物教学为例，阐述了该法的优越性．     

1914年的“梦游者”

<正>盘点过去一年,"梦"不愧是全世界最热门的词之一。2013年12月底,《纽约时报》评出年度十大好书。其中非虚构类图书《梦游者:1914年欧洲如何走向战争》(The Sleepwalkers:How Europe Went to War in 1914)位列其中。当然这本书并不是教人如何做梦的,而是用"梦游者"来比喻100年前的欧洲列强在"梦游状态"中把自己的国家引入第一次世界大战。     

英语V+To+Infinitive与V+To+V-ing结构的对比分析

英语v+to+infinitive与v+to+v-ing结构极易发生混淆。在句法上,v+to+infinitive结构中的to+infinitive要么是CP,要么是TP,而v+to+v-ing结构中的to+v-ing是介词短语PP。从语义角度来说,我们可以用主动词提示的时间做参照,to+infinitive所蕴含事件的时间要么发生在主动词时间之后或是与之同时发生,而to v-ing所蕴含的事件可以发生在主动词时间之前,之后或同时发生。另外,与to+infinitive结构不同的是v-ing结构更加倾向强调所发生事件的内部组成成分,所持续的时间和展开的方式等。     

The cost implementation of adoption of e-commerce in SMES

Introduction
SMES are generally considered to be flexible to adapt to e-commerce. They are considered to be a major component of all economies and are generally considered to be flexible, adaptive and innovative organizations （Rao et al, 2003）. E-commerce is introduced to SMES and has a rapid growth of adoption. The open structure and low cost of using Internet provide a chance to communicate and collecting information conveniently to buyers and sellers.     

Suggestions on How to Learn English at College

Many students don＇t know how to learn English at college. Without a goal in life and unable to manage their time, they are likely to idle away their youth. This paper intends to offer some suggestions to students on how to learn English at college, and hopefully they will experience the satisfaction and pleasure of learning English.     

NET平台下LINQ TO SQL关键技术的实践研究

LINQ to SQL在对象领域和数据领域之间架起了一座桥梁,利用LINQ to SQL可以简化对SQL Server数据库的操作。本文介绍了LINQ to SQL技术要点,阐述了创建LINQ to SQL实体类的映射的步骤方法及注意事项,给出了LINQ to SQL访问SQL Server数据库的查询、删除、修改、更新操作要点及实现的核心代码。     

分子轨道理论中的一些能量关系

分子轨道理论中,体系的总能量既可写成 E=2 sum from i to nε_1-sum from i to n sum from j to n(2J_(ij)-K_(ij))+sum from A相似文献   

情态助动词用法小结

情态助动词除了在句子中具有语法功能外,它们本身也具有意义。这些意义可以概括为能力、许可、推测、意愿、建议、义务、习惯和胆敢。本文试就情态助动词的这几个方面的意义及用法作一小结。 一、表示能力 表示能力的情态助动词只有can和could,can用于现在或将来,could用于过去: 1) He can speak English but he can't write it very well. 2) Can you come to the party on Saturday? 3) I couldn't get the tickets yesterday.     

A NEW INTEGRATION WITH RESPECT TO A VECTOR MEASURE AND ITS PROPERTIES

We introduce a new integration with respect to a vector measure, which may be considered the generalization of a line integration with respect to coordinates in classical calculus. we disscuss its properties and investigate the relationship between an integration with respect to a vector measure and one with respect to the variation of the vector measure, which is similar to the relationship between a line integration with respect to coordinates and one with respect to arc length.     

Vulnerability assessment of areas affected by Chinese cryospheric changes in future climate change scenarios

Using the definition of vulnerability provided by the Intergovernmental Panel on Climate Change,this paper assesses the vulnerability of areas affected by Chinese cryospheric changes from 2001 to 2020 and from 2001 to 2050 in A1 and B1scenarios.Seven indices are used in the vulnerability assessment:glacial area fraction,interannual variability of permafrost depth,interannual variability of surface snow area fraction,interannual variability of surface runoff,interannual variability of surface temperature,interannual variability of vegetation growth,and interannual variability of the human development index.Assessment results show that the overall vulnerability of the studied areas in China increases from east to west.The areas in the middle and eastern parts of China are less vulnerable compared with western parts and parts of the Tibetan Plateau.The highest vulnerability values are found from 1981 to 2000,and the least ones are found from 2001 to 2050.The vulnerable areas increase from the period of 1981 to 2000 to the period of 2001 to 2050,and the less vulnerable areas decrease.The highly vulnerable areas increase from the period of 1981 to 2000 to the period of 2001 to 2020 and then decrease from the period of 2001 to 2020 to the period of 2001 to 2050.This decrease in vulnerability is attributed to the decrease in exposure and sensitivity to Chinese cryospheric changes along with a concomitant increase in adaptation.     

Becoming a first-class research university through creative innovation

After half a century of focussed hard work, the University of Science and Technology of China （USTC） recently celebrated the 50th anniversary of its founding. President Hu Jingtao sent a con- gratulatory letter, encouraging USTC to strengthen its sense of mission and responsibility, to aim for cutting edge scientific and technological research, to serve China＇s strategic development needs, to creatively teach and research and to do all possible to build a world-class research university.     

The Methods Employed in Color Words Translation

Different pragmatic meanings of color words based on different cultural correspondence between source and target language, hence a translator is obliged to decide which aspect of meaning should be conveyed to the receiver. The purpose of this paper is to tell how to use cultural connotation to translate color words on the basis of functional equivalence and pragmatic meaning. Mistakes can be optimally avoided while sticking to this principle.     

DESIGN OF INTERNETWORK ANAGEMENT BASED ON VLANs

Implement VLANs essentially creating smaller broadcast domains at layer 2, means that broadcasts sent out from a node in one VLAN won＇ t be forwarded to ports configured to belong to a different VLAN. In this paper, we assigning users to VLAN groups on a switch, this help to gain the flexibility to add only the users you want into that broadcast domain regardless of their physical location. This setup can also work to block broadcast storms caused by a faulty network interface card （NIC） as well as prevent an intermediate device from propagating broadcast storms throughout the entire internetwork.     

Climate change over southern Qinghai Plateau in the past 500 years recorded in Sabina tibetica tree rings

Two tree ring-width chronologies of Sabina tibetica were developed based on cores sampled in Qumalal and Zhiduo, southern Qinghai Plateau. The response function analysis showed that the chronologies were sensitive to temperature and precipitation from April to June in the plateau. Moisture index (MI) was defined, reconstructed and extended back to AD 1550. The cross-validation method was used to check the stability of the calibration equation, and the result indicated that the equation was stable. Six severe dry periods were found in this region in the past 453-year reconstruction, which were 1592 to 1610, 1649 to 1665, 1687 to 1697, 1740 to 1750, 1818 to 1829 and 1918 to 1933. Five severe wetting periods were 1669 to 1682, 1700 to 1709, 1800 to 1814, 1898 to 1909 and 1935 to 1950. Spectrum analysis indicated that there existed long-term cycles of 60.4 and 53.4 a, solar cycle of 11 a and short-term cycles of 8, 6 and 4 a in the reconstructed series.     

Traffic simulation and forecasting system in Beijing

Transport system is a time-varying, huge and complex system. In order to have the traffic management department make pre-appropriate traffic management measures to adjust the traffic management control program, and release travel information to travelers, to provide optimal path options to ensure that the transport system operates efficiently and safely, we have to monitor the changing of the state of road traffic and to accurately evaluate the state of the traffic, then to pre-predict the future state of traffic. This paper represents the construction of the road traffic flow simulation including the logical structure and the physical structure, meanwhile introduces the system functions of forecasting system in Beijing.     

Computer Multimedia Used in English Newspaper Reading

English-teaching has great improvement with the help of Information Technology.Computers give lots of convenience to second-language teaching,which is really different from traditional teaching model.It combines sound,picture,video,camera and even telephone together to realize the environment language-learners need.Therefore,that＇s valuable to solve how to teach with computer multimedia and how to make it well-served us teachers.