一般现在时。用于说明研究目的、叙述研究内容、描述结果、得出结论、提出建议或讨论等。分别举例如下:This study(investigation) is (conducted, undertaken) to…The anatomy of secondary xylem(次生木质部) in stem of Davidia involucrata (珙桐) and Camptotheca acuminata (喜树) is compared. The result shows(reveals)…,It is found that…The conclusions are…The author suggests….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。
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、永恒真理的,而只是当时如何如何;所描述的研究过程也明显带有过去时间的痕迹。
现在完成时和过去完成时。完成时少用,但不是不用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.?
主动语态。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。
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) 英文摘要的人称。原来摘要的首句多用第三人称This paper…等开头例如: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。
应避免一些常见的错误。
冠词。主要是定冠词the易被漏用。the用于表示整个群体、分类、时间、地名以外的独一无二的事物、形容词最高级等较易掌握,用于特指时常被漏用。这里有个原则,即当我们用the时,听者或读者已经确知我们所指的是什么。例如:The author designed a new machine.The machine is operated with solar energy.?要注意区分a和an,如an X ray.
数词。避免用阿拉伯数字作首词,如:Three hundred Dendrolimus tabulaeformis larvae are collected…中的 Three hundred?不要写成300.?