涉及到公认事实、自然规律、永恒真理等，当然也要用一般现在时 。2）一般过去时.用于叙述过去某一时刻（时段）的发现、某一研究过程（实验、观察、调查、医疗等过程） 。
例如：The heat pulse technique was applied to study the stemstaflow （树干液流） of two main deciduous broadleaved tree species in July and August,1996.需要指出的是，用一般过去时描述的发现、现象，往往是尚不能确认为自然规律、永恒真理 。3）现在完成时和过去完成时.完成时少用，但不是不用.现在完成时把过去发生的或过去已完成的事情与现在联系起来，而过去完成时可用来表示过去某一时间以前已经完成的事情，或在一个过去事情完成之前就已完成的另一过去行为 。
例如：Concrete has been studied for many years.Man has not yet learned to store the solar energy 。2、语态：采用何种语态，既要考虑摘要的特点，又要满足表达的需要 。
一篇摘要很短，尽量不要随便混用，更不要在一个句子里混用 。1）主动语态.现在主张摘要中谓语动词尽量采用主动语态的越来越多，因其有助于文字清晰、简洁及表达有力 。
The author systematically introduces the history and development of the tissue culture of poplar 比 The history and development of the tissue culture of poplar are introduced systematically语感要强.必要时，The author systematically都可以去掉，而直接以Introduces开头 。2）被动语态 。
以前强调多用被动语态，理由是科技论文主要是说明事实经过，至于那件事是谁做的，无须一一证明 。事实上，在指示性摘要中，为强调动作承受者，还是采用被动语态为好 。
即使在报道性摘要中，有些情况下被动者无关紧要，也必须用强调的事物做主语 。例如：In this case,a greater accuracy in measuring distance might be obtained 。
3、人称：原来摘要的首句多用第三人称This paper等开头，现在倾向于采用更简洁的被动语态或原形动词开头 。例如：To describe,To study,To investigate,To assess,To determine,The torrent classification model and the hazard zone mapping model are developed based on the geography information system 。
行文时最好不用第一人称，以方便文摘刊物的编辑刊用 。掌握一定的遣词造句技巧的目的是便于简单、准确的表达作者的观点，减少读者的误解 。
1）用词力求简单，在表达同样意思时，尽量用短词代替长词，以常用词代替生僻词 。但是当描述方法、步骤时，应该用狭义词代替广义词 。
6.论文英文摘要怎么写Local the Party paper as major media of locality , transmit party and country , Party committee of a higher level , voice of government, transmit local Party Committee and government specially in the Central Party Committee of implementation , the Party committee of a higher level and government's great principles and policies concrete measure, there are guidance and authoritativeness that other medias can't compare , so often become the focus that local audiences pay close attention to. But enter after the socialist market economy, journalism structure of our country take place a obvious one, enough to influence local the Party paper change , news report of result. Journalism has already developed into much varieties taking the Party paper as the centre, multi-level three-dimensional structure from a structure of party's declaration form, the newspaper in evening paper , city newspaper , life newspaper , specialized newspaper ,etc. doubles and redoubles, the network, this kind of new combining a large amount of transmission information fast of media of short information of cell phone at the same time, the foreign media enters the native country and seizes the market of native country. This kind of change and growth make audiences choose the information channel of the news to increase, the degree of freedom increases day by day. So local the Party paper irreplaceable status , news of information issue receive the severe challenge. So how strengthen local key competitiveness of the Party paper new period, become we want problem that solve urgently. Focus on this question to describe from content , form of the news report , journalists , reader's marriage partner and these five respects of market mechanism of the news report, is it can prove our country now local state of development of the Party paper and predicament that run into and for strengthen key competitiveness should what kind of efforts does it make to expect. Keyword: Local the Party paper; Core; Competitiveness ; Market; Readability; Affinity 。