例如：Many of the lakes and wetlands in the region are located in craters or valleys blocked by early Pliocene lava flows (Ollier & Joyce, 1964). Garcia (1993) suggested that under certain conditions, an individual’s deposit income is the same as the income from purchased national debt, thus changes in the amount of bank loans and deposits caused by changes in the amount of reserves will eventually affect the bond price.
例如：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）
材料与方法（Materials and Methods）
（例1） Total phosphorous (TP) and total nitrogen (TN) were measured in the laboratory using standard procedures.
（例2）The standard protocol was followed for the preparation of the media from stock solutions.
例如：（例1）Overall, more than 70% of the insects collected were non-phytophagous.
（例2） Following activation of NT oocytes with strontium, the cell cycle resumed in both groups.
例如：（例1） Figure 1 displays the comparative variation in the morphology of donor chromatin in both age groups of oocytes.
（例2） Table 1 below shows the stream flows calculated for each stream using Equation 1. 图1和表1表达的论文写作时的状态，所以要用现在时。
例如：Removal of vegetation for agricultural purposes appears to negatively affect the water quality of streams.
例如：（例1）Weight increased as the nutritional value of feed increased. These results suggestthat feeds higher in nutritional value contribute to greater weight gain in livestock.
（例2）Leaf carbon and phenolic content did not differ across sites, indicating that the response of secondary plant chemicals such as phenolics to water is complex.
可用多种时态，使用过去时强调过去的研究成果，并可采用现在时或将来时表达未来的研究方向或研究前景。 例如：Although the study found evidence of tillage and irrigation within the study area, from the data collected it was not possible to determine if the effects of agriculture upstream cause (or caused) higher levels of total nitrogen downstream. Further studies are therefore necessary to determine the effects of agriculture on the health of Stringybark Creek.