在撰写科技论文时,你已经完成了研究、设计、和试验工作,所以在描写自己的研究方法的章节里,在叙述研究结果的章节里,动词都应该用过去时。例句: We hypothesized that adults would remember more items than children. We extracted tannins from the leaves by bringing them to a boil in 50% methanol. In experiment 2, response varied.
在描述别人的相关工作时,动词时态要用过去时。
在引用别人已完成的工作时,动词时态要用过去时。例句:
Smith (2008) reported that adult respondents in his study remembered 30 percent more than children. 这里 Smith 的研究是在过去做的,他的发现具有领域的特殊性。 Previous research showed that children confuse the source of their memories more often than adults (Lindsey et al., 1991). 这项以前的研究结果在今天已广为接受。
当描述一些已经过时或失效的科研结果时,动词要使用过去时。例句:
Nineteenth-century physicians held that women got migraines because they were "the weaker sex," but current research shows that the causes of migraine are unrelated to gender. 注意这里从过去时态过渡到现在时态。
We chose Vietnam for this study because it has a long coastline.
这里“选择”用过去时,而“有”则用现在时。
在引用文章内部的图表时要用现在时。例句:
Table 3 shows that the main cause of weight increase was nutritional value of the feed.
图表3表达的是一个事实,而且这个事实不会因为读者不同而改变,所以要用现在时。
在结论中的讨论,描绘新方法、新结果的意义时可以用现在时。例句:
Weight increased as the nutritional value of feed increased. These results suggest that feeds higher in nutritional value contribute to greater weight gain in livestock.