Portuguese conjugation explanation

Stem change: -o- → -u-

<p>For a specific group of verbs ending in <strong style="font-style: italic">-ir</strong> with the vowel <span style="font-style: italic">o</span> in their stem, a spelling change occurs in the present tense key forms.</p>

<p>For these verbs, the <strong><span style="font-style: italic">o</span> changes to <span style="font-style: italic">u</span></strong> in the first person singular (S/1, <span style="font-style: italic">eu</span>) of the

<a class="conjugation_explanation_link_intext" href="/study/tenseGuideForTense/1/" target="_blank">Present Indicative</a>

. The rest of the forms in the Present Indicative remain regular (keeping the <span style="font-style: italic">o</span>).</p>

<div class="conjugation_explanation_title">Common Verbs</div>

<p>The most common verbs following this pattern are:</p>

<ul>

<li>

<a class="conjugation_explanation_link_intext verb_link" href="/study/conjugations/por/dormir/" title="Click to see conjugations for dormir" target="_blank">dormir</a>

(<span style="font-style: italic">to sleep</span>)</li>

<li>

<a class="conjugation_explanation_link_intext verb_link" href="/study/conjugations/por/cobrir/" title="Click to see conjugations for cobrir" target="_blank">cobrir</a>

(<span style="font-style: italic">to cover</span>)</li>

<li>

<a class="conjugation_explanation_link_intext verb_link" href="/study/conjugations/por/descobrir/" title="Click to see conjugations for descobrir" target="_blank">descobrir</a>

(<span style="font-style: italic">to discover</span>)</li>

<li>

<a class="conjugation_explanation_link_intext verb_link" href="/study/conjugations/por/engolir/" title="Click to see conjugations for engolir" target="_blank">engolir</a>

(<span style="font-style: italic">to swallow</span>)</li>

<li><span style="font-style: italic">tossir</span> (<span style="font-style: italic">to cough</span>)</li>

</ul>

<p>In the table below, notice how the first person singular uses <span class="green_emphasis">u</span>, while the second person returns to <span style="font-style: italic;">o</span>:</p>

<div class="study_conjugations_tense_container">

<a class="study_conjugations_tense_label box_label tense_box no_dark_mode " href="/study/tenseGuideForTense/1/" target="_blank" title="Open tense guide">Presente</a>

<div class="study_conjugations_conjugation conjugations_table two_columns">

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

eu

</span><span class="irregular_conjugation" title="irregular conjugation">durmo<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

tu

</span>dormes

</span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

ele

</span>dorme

</span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

nós

</span>dormimos

</span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

vós

</span>dormis

</span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

eles

</span>dormem

</span>

</div>

</div>

</div>

</div>

<div class="conjugation_explanation_title">Derived Tenses</div>

<p>Crucially, this change in the first person singular (<span style="font-style: italic">eu durmo</span>) serves as the stem for the entire

<a class="conjugation_explanation_link_intext" href="/study/tenseGuideForTense/8/" target="_blank">Present Subjunctive</a>

. Therefore, all forms in the Present Subjunctive are spelled with a <strong><span style="font-style: italic">u</span></strong>.</p>

<div class="study_conjugations_tense_container">

<a class="study_conjugations_tense_label box_label tense_box no_dark_mode " href="/study/tenseGuideForTense/8/" target="_blank" title="Open tense guide">Presente do Subjuntivo</a>

<div class="study_conjugations_conjugation conjugations_table two_columns">

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

que eu

</span><span class="irregular_conjugation" title="irregular conjugation">durma<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

que tu

</span><span class="irregular_conjugation" title="irregular conjugation">durmas<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

que ele

</span><span class="irregular_conjugation" title="irregular conjugation">durma<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

que nós

</span><span class="irregular_conjugation" title="irregular conjugation">durmamos<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

que vós

</span><span class="irregular_conjugation" title="irregular conjugation">durmais<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

que eles

</span><span class="irregular_conjugation" title="irregular conjugation">durmam<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

</div>

</div>

<p>This also affects the

<a class="conjugation_explanation_link_intext" href="/study/tenseGuideForTense/11/" target="_blank">Imperative</a>

forms that are derived from the subjunctive (S/3, P/1, P/3), as well as the negative imperative.</p>

<div class="study_conjugations_tense_container">

<a class="study_conjugations_tense_label box_label tense_box no_dark_mode " href="/study/tenseGuideForTense/11/" target="_blank" title="Open tense guide">Imperativo Afirmativo</a>

<div class="study_conjugations_conjugation conjugations_table two_columns">

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span class="study_conjugations_pronoun conjugation_pronoun">---</span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

(tu)

</span>dorme

</span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

(você)

</span><span class="irregular_conjugation" title="irregular conjugation">durma<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

(nós)

</span><span class="irregular_conjugation" title="irregular conjugation">durmamos<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

(vós)

</span>dormi

</span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

(vocês)

</span><span class="irregular_conjugation" title="irregular conjugation">durmam<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

</div>

</div>

<div class="conjugation_explanation_title">Exceptions</div>

<p>Not all verbs ending in <strong style="font-style: italic">-ir</strong> with an <span style="font-style: italic">o</span> follow this rule. Special attention should be paid to:</p>

<ul>

<li>

<p><strong>Irregular Verbs:</strong> Common irregular verbs have their own unique stems. For example,

<a class="conjugation_explanation_link_intext verb_link" href="/study/conjugations/por/sorrir/" title="Click to see conjugations for sorrir" target="_blank">sorrir</a>

(<span style="font-style: italic">to smile</span>) follows the conjugation of

<a class="conjugation_explanation_link_intext verb_link" href="/study/conjugations/por/rir/" title="Click to see conjugations for rir" target="_blank">rir</a>

, changing to <span style="font-style: italic;">io</span>.</p>

<div class="study_conjugations_tense_container">

<a class="study_conjugations_tense_label box_label tense_box no_dark_mode " href="/study/tenseGuideForTense/1/" target="_blank" title="Open tense guide">Presente</a>

<div class="study_conjugations_conjugation conjugations_table two_columns">

<div class="study_conjugations_forms conjugation_forms highlighted_conjugation">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

eu

</span><span class="irregular_conjugation" title="irregular conjugation">sorrio<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

tu

</span><span class="irregular_conjugation" title="irregular conjugation">sorris<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

ele

</span><span class="irregular_conjugation" title="irregular conjugation">sorri<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

nós

</span>sorrimos

</span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

vós

</span><span class="irregular_conjugation" title="irregular conjugation">sorrides<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

<div class="study_conjugations_forms conjugation_forms">

<div class="conjugation_form">

<span><span class="study_conjugations_pronoun conjugation_pronoun">

eles

</span><span class="irregular_conjugation" title="irregular conjugation">sorriem<span class="irregularity_circle">&#9679;</span></span></span>

</div>

</div>

</div>

</div>

</li>

<li>

<p><strong>Derivatives of Vir:</strong> Verbs like <span style="font-style: italic">convir</span> or <span style="font-style: italic">provir</span> follow the conjugation of

<a class="conjugation_explanation_link_intext verb_link" href="/study/conjugations/por/vir/" title="Click to see conjugations for vir" target="_blank">vir</a>

(<span style="font-style: italic">venho</span>), not the <span style="font-style: italic">o</span> &#8594; <span style="font-style: italic">u</span> rule.</p>

</li>

<li>

<p><strong>Fully Regular Verbs:</strong> A few obscure verbs, such as <span style="font-style: italic">colorir</span> (<span style="font-style: italic">to color</span>) or <span style="font-style: italic">eclodir</span> (<span style="font-style: italic">to hatch</span>), are completely regular and keep the <span style="font-style: italic">o</span> (e.g., <span style="font-style: italic">eu coloro</span>), though these forms are rarely used.</p>

</li>

</ul>

<p>For a similar stem change pattern involving the letter <span style="font-style: italic">e</span>, see:

<a class="conjugation_explanation_link_intext" href="/conjugationExplanation/portuguese_stem_change_e_ir/" target="_blank">Stem change: -e- &#8594; -i-</a>

.</p>