There are 16 kinds of English predicate verb tenses, among which three are mainly used in SCI papers: simple present tense, simple past tense and future tense. If the tense in the paper is used improperly, it will often change the meaning of the author and affect the understanding of experts and readers.

Usually, SCI papers will include abstracts, materials and methods, results, conclusions, discussions, thanks and references, most of which are similar, such as abstracts and supplementary data.

Next, I will introduce English tenses commonly used in different parts according to the framework of this article.

First of all, we need to know three basic reference criteria for choosing different English tenses in papers:

1. The simple present tense is mainly used to describe the unrestricted objective existence facts, and generally exists in the description of feelings, States and relationships when writing a paper, as well as in gratitude. It is worth noting that for the achievements published by others, out of respect, the past tense is not used, but the simple present tense is used.

2. The simple past tense is mainly used to describe the work done by the author, such as materials, methods and structures.

3. The general future tense is mainly used for the work or state after writing the paper, such as proposing the next research direction.

Knowing these three basic reference standards, I will analyze what tenses to use from different parts of the paper:

abstract:

It reflects our own research results, so we use the simple past tense.

Introduction:

The research background in 1. Introduction usually refers to the widely accepted principles or facts in related disciplines and the importance of your research, and usually adopts the simple present tense.

Example: Genomics provides cruel information for rational drug design.

2. In the introduction, you can also quote some research results related to your research. To show that you still believe in the correctness and relevance of the research results, you can use the simple present tense even though it was a long time ago.

Example: Garcia (1993) pointed out that under certain conditions, individuals' income from deposits is the same as that from purchasing government bonds, so the changes in bank loans and deposits caused by the changes in reserves will eventually affect bond prices.

Corresponding to the above items, if the research results are outdated or invalid, the simple past tense is used.

Example:/kloc-Physicists in the 0/9th century thought that women suffered from migraine because they were "the gender of the wearer", but the current research shows that the cause of migraine has nothing to do with gender.

Materials and methods:

This part is a description of my previous work, so I use the simple past tense.

Example 1: Total phosphorus (TP) and total nitrogen (TN) were measured in the laboratory using standard procedures.

Example 2: Culture medium was prepared from stock solution according to standard protocol.

Results:

There are two situations here. If it is the result of describing the contents of the chart, it indicates the state when writing the paper, using the simple present tense.

Example 1: Figure 1 shows the comparative differences of donor chromatin morphology in oocytes of two age groups.

Example 2: The following table 1 shows the river flow calculated for each river using the equation 1.

If you describe your research results, you will use the simple past tense to elaborate.

Example 1: Overall, more than 70% of the collected inserts are non-botanical.

Example 2: With the passage of time, after the activation of ntooo cells, the cell cycle of both groups recovered.

Discussion:

There are also two situations in which the simple present tense is used to express the meaning of research results.

For example, removing vegetation for agricultural purposes seems to have a negative impact on the water quality of rivers.

Use the simple past tense when summarizing the research results, and use the simple present tense when explaining and discussing the research results.

Example 1: As the nutritional value of feed increases, the weight increases. The results showed that feed with high nutritional value was helpful to improve immunity. The weight of livestock has increased. This example uses the simple past tense when describing the experimental discovery and the simple present tense when discussing the significance of this discovery.

Example 2: There is no difference in the contents of leaf carbon and phenol in different places, indicating that the reaction of secondary plant chemicals such as phenol to water is complicated. This example uses the simple present tense to show that the author firmly believes in the correctness of his research results and conclusions.

Conclusion:

Use the simple past tense when emphasizing the past research results, and use the simple present tense or future tense when looking forward to the future research direction or prospect.

For example, although the study found evidence of cultivated land and the study area, from the collected data, it is impossible to determine whether the influence of upstream agriculture led to the increase of total nitrogen level in the downstream. Therefore, further research is needed to determine the impact of agriculture on the health of Stringybark Creek.

So much for today's questions about English phonetics in SCI papers, which should be more detailed. I hope you can be clear when you translate, and don't be confused by this question.