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Verb tenses</span></div> <div id="content" class="id-484 "> <div> <nav class="nav-article nav-buttons"> <ul class="menu"> <li class="item-145 deeper parent"><span class="separator">About A&A</span> <ul><li class="item-137"><a href="/about-aa/aims-and-scope" >Aims and scope</a></li><li class="item-143"><a href="/about-aa/history" >History</a></li><li class="item-136"><a href="/about-aa/editors-of-aa" >Editors of A&A</a></li><li class="item-140"><a href="/about-aa/board-of-directors" >Board of Directors</a></li><li class="item-138"><a href="/about-aa/indexed-in" >Indexed in</a></li><li class="item-139"><a href="/about-aa/copyright" >Copyright</a></li><li class="item-162"><a href="/images/stories/leaflet/aa_leaflet.pdf" target="_blank" >A&A leaflet (PDF)</a></li><li class="item-530"><a href="https://www.edpsciences.org/images/stories/librarians/EDP-AA-S2O.pdf" target="_blank" >A&A S2O leaflet (PDF)</a></li><li class="item-197"><a href="/about-aa/masthead" >Masthead</a></li></ul></li><li class="item-424 deeper parent"><span class="separator">Browse articles</span> <ul><li class="item-427"><a href="/component/issues/?task=all" >All volumes</a></li><li class="item-429"><a href="/component/list/?task=topic" >Special issues</a></li><li class="item-432"><a href="/component/forthcoming/" >Forthcoming</a></li><li class="item-435"><a href="/highlights" >Highlights</a></li><li class="item-221"><a href="/2024-press-releases" >Press releases</a></li><li class="item-533"><a href="/component/issues/?task=images" >Featured images</a></li></ul></li><li class="item-396 active deeper parent"><a href="/for-authors" >For authors</a><ul><li class="item-161 deeper parent"><span class="separator">Author information</span> <ul><li class="item-186"><a href="/for-authors/author-information/paper-organization" >Paper organization</a></li><li class="item-232"><a href="/for-authors/author-information/news-from-the-editorial-office" >News from the Editorial Office</a></li><li class="item-192"><a href="/for-authors/author-information/page-charges" >Page charges</a></li><li class="item-173"><a href="/for-authors/author-information/acceptance-stage" >Acceptance stage</a></li><li class="item-159"><a href="/for-authors/author-information/production-stage" >Production stage</a></li><li class="item-233"><a href="/for-authors/author-information/copyright" >Copyright</a></li><li class="item-231"><a href="/for-authors/author-information/open-access" >Open Access</a></li><li class="item-196"><a href="/doc_journal/instructions/aadoc.pdf" target="_blank" >Author's guide (PDF)</a></li></ul></li><li class="item-189 active deeper parent"><span class="separator">Language editing</span> <ul><li class="item-502"><a href="/for-authors/language-editing/1-introduction" >1. Introduction</a></li><li class="item-472"><a href="/for-authors/language-editing/2-main-guidelines" >2. Main guidelines for A&A style</a></li><li class="item-475"><a href="/for-authors/language-editing/3-general-structure" >3. General structure</a></li><li class="item-478"><a href="/for-authors/language-editing/4-uk-versus-us-spelling-and-grammar" >4. UK versus US spelling and grammar</a></li><li class="item-481"><a href="/for-authors/language-editing/5-punctuation-and-style-concerns-regarding-equations-figures-tables-and-footnotes" >5. Punctuation and style concerns regarding equations, figures, tables, and footnotes</a></li><li class="item-484 current active"><a href="/for-authors/language-editing/6-verb-tenses" >6. Verb tenses</a></li><li class="item-487"><a href="/for-authors/language-editing/7-general-hyphenation-guide" >7. General hyphenation guide</a></li><li class="item-490"><a href="/for-authors/language-editing/8-common-editing-issues" >8. Common editing issues</a></li><li class="item-493"><a href="/for-authors/language-editing/9-measurements-and-their-descriptions" >9. Measurements and their descriptions</a></li><li class="item-496"><a href="/for-authors/language-editing/10-suggested-resources-for-more-tips-on-language-editing-in-the-sciences" >10. Suggested resources for more tips on language editing in the sciences</a></li><li class="item-499"><a href="/images/stories/author/EnglishGuide-2021.pdf" target="_blank" >Full Guide (PDF file)</a></li></ul></li><li class="item-178 deeper parent"><span class="separator">LaTeX issues</span> <ul><li class="item-370"><a href="/for-authors/latex-issues/texnical-background-information" >TeXnical background information </a></li><li class="item-369"><a href="/for-authors/latex-issues/the-preamble-of-your-tex-file" >The preamble of your TEX file</a></li><li class="item-371"><a href="/for-authors/latex-issues/the-manuscript-header" >The manuscript header</a></li><li class="item-391"><a href="/for-authors/latex-issues/including-author-names-using-non-roman-alphabets" >Including author names using non-Roman alphabets</a></li><li class="item-372"><a href="/for-authors/latex-issues/the-main-text" >The main text</a></li><li class="item-373"><a href="/for-authors/latex-issues/figures" >Figures</a></li><li class="item-374"><a href="/for-authors/latex-issues/tables" >Tables</a></li><li class="item-375"><a href="/for-authors/latex-issues/multi-media" >Multimedia </a></li><li class="item-376"><a href="/for-authors/latex-issues/references" >References </a></li><li class="item-377"><a href="/for-authors/latex-issues/typography" >Typography</a></li><li class="item-378"><a href="/for-authors/latex-issues/appendices" >Appendices </a></li><li class="item-380"><a href="/for-authors/latex-issues/astronomical-objects-linking-to-databases" >Astronomical objects: linking to databases </a></li><li class="item-381"><a href="/for-authors/latex-issues/latex-examples" >LaTeX examples</a></li><li class="item-466"><a href="/for-authors/latex-issues/information-files" >Information files</a></li></ul></li><li class="item-456"><a href="https://writingstudio.aws.edpsciences.org/login" target="_blank" >Writing studio</a></li><li class="item-459"><a href="/for-authors/submit-an-article" >Submit an article</a></li></ul></li><li class="item-440"><a href="/component/journal_price/" >Subscriber information</a></li><li class="item-514"><a href="/subscribe-to-open-faqs" >Subscribe to Open (S2O) FAQs</a></li><li class="item-437"><a href="/component/services/" >Reader's services</a></li><li class="item-127"><a href="/news" >News</a></li></ul> </nav> <div id="system-message-container"> </div> <div class="item-page"> <h1> 6. Verb tenses </h1> <p>You are likely to find yourself shifting between tenses in your paper depending on what aspect of your findings you are discussing. In general, A&A style uses the present tense to describe general facts, findings, truths, methods, and results from papers published within the last ten years. We use the past tense to describe the specific steps of the method used in your study or another study by a different author or group of authors. Here are some tips on when to use the past tense and when to use the present.</p> <h2 id="chap6.1">6.1 Present simple and past simple</h2> <p>Use the <strong>present simple</strong> for: </p> <ul class="simple"> <li>statements of fact and general truths</li> <li>general findings from other authors, particularly recent ones (from the last ten years)</li> <li>general methods used in the field (not the specific steps you used in your study)</li> <li>general descriptions of your results and findings, including any discussions or conclusions</li> <li>descriptions of tables and figures included in the paper</li> </ul> <p>Time markers for the present include: now, usually, often, currently, at present, in this paper, etc.</br> The context will also indicate the tense that is appropriate for each part of your paper. The introduction, for example, tends to offer the reader a <strong>general</strong> background for the current study so it is typically written in the present tense.</p> <p><strong>Examples:</strong></p> <ul class="no-item"> <li><span class="ico-font ico-valid"></span> In the usual reduction procedure, the data are measured and flux-calibrated.</li> <li><span class="ico-font ico-valid"></span> Herschel images allow us to detect new YSOs.</li> <li><span class="ico-font ico-valid"></span> In this paper, we find that the emission could be fully non-thermal at 5 GHz.</li> </ul> <p>Use the <strong>past simple</strong> for: </p> <ul class="simple"> <li>specific steps you took as part of your method for your study (not general methods)</li> <li>specific steps taken as part of a method by other authors and scientists (not general methods)</li> <li>specific methods taken by other authors as well as their findings from studies in the distant past (e.g., more than ten years ago)</li> </ul> <p>The past tense is frequently used in the body of the paper where you describe the <strong>specific</strong> actions you took in your study to achieve your final results, such as: we took, we carried out, we measured, we calibrated, we used, we observed, we calculated, we deduced, we assumed, we concluded.</p> <p><strong>Examples:</strong></p> <ul class="no-item"> <li><span class="ico-font ico-valid"></span> In our study, we measured and flux-calibrated the data.</li> <li><span class="ico-font ico-valid"></span> We detected 16 YSOs based on the Herschel images.</li> <li><span class="ico-font ico-valid"></span> Using this method, we found that the emission was fully non-thermal at 5 GHz.</li> </ul> <p>When describing your findings in the present tense, make sure that you also use the <strong>present</strong> for <strong>recent</strong> or <strong>current</strong> (within the last ten years) findings from other authors. Using the past tense when referring to the work of other authors could suggest that their findings are incorrect or out of date. Their specific methods, however, should remain in the past tense.</p> <h2 id="chap6.2">6.2 Present perfect and past perfect</h2> <p>These tenses are used to describe actions that occur over an extended period of time or at an unspecified point in time.They are generally <strong>not particularly useful</strong> in scientific writing.</p> <p><strong>Examples:</strong></p> <ul class="no-item"> <li><span class="ico-font ico-valid"></span> Astronomers have used many different methods to study the Milky Way.</li> <li><span class="ico-font ico-valid"></span> The authors had already published their paper by the time we finished ours.</li> </ul> <p>There is also the <strong>present perfect continuous tense</strong>, which is used to describe an action that began in the past, continues in the present, and may continue into the future. Again, this tense is <strong>rarely</strong> necessary when writing a scientific paper.</p> <p><strong>Example:</strong></p> <ul class="no-item"> <li><span class="ico-font ico-valid"></span> The researchers’ results have been useful in providing a background for our own study.</li> </ul> <p><strong>Note:</strong> This tense can be used with phrases that serve as indicators of time, such as “in the past few years, in recent years, over the past few years” to extend the action through a period of time.</p> <p><strong>Example:</strong></p> <ul class="no-item"> <li><span class="ico-font ico-valid"></span> In recent years, several Seifert 2 galaxies have been discovered.</li> </ul> <h2 id="chap6.3">6.3 Present continuous and past continuous</h2> <p>These tenses are not recommended as there is <strong>seldom</strong> any need for the present or past continuous <strong>unless</strong> you are describing an ongoing action in the context of a simple action. <p><strong>Examples:</strong></p> <ul class="no-item"> <li><span class="ico-font ico-valid"></span> We conducted our study as night was falling.</li> <li><span class="ico-font ico-valid"></span> It was proving difficult to calibrate the instrument due to environmental effects.</li> </ul> <h2 id="chap6.4">6.4 Future</h2> <p>In certain instances, you may use the future tense to describe upcoming studies or new equipment.</p> <p><strong>Examples:</strong></p> <ul class="no-item"> <li><span class="ico-font ico-valid"></span> Crab pulsar rotation periods will be further examined in a forthcoming paper.</li> <li><span class="ico-font ico-valid"></span> The JWST will provide greatly improved resolution and sensitivity.</li> </ul> <p>Once in a while, you might find yourself needing to alternate between tenses when discussing things that happened at various points in time.</p> <p><strong>Example:</strong></p> <ul class="no-item"> <li><span class="ico-font ico-valid"></span> The Hubble deep field consists of 300 images that were taken in 1995. 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