Why does “dû” have a circumflex accent, but not “eu”, “pu”, “su”, “vu”, or “voulu”? If you’ve studied French verbs, you’ve probably noticed that the past participle of devoir is dû, with a circumflex accent over the u. That might seem unusual when you compare it to other common past participles:

• avoir → eu
• pouvoir → pu
• savoir → su
• voir → vu
• vouloir → voulu

None of these take an accent. So why does devoir stand out with dû?

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The Historical Reason: Distinguishing Homophones

The circumflex in dû does not affect pronunciation. It is silent. It exists for a purely orthographic reason: to distinguish dû (the past participle of devoir) from the homophone du, which is a contraction of de + le meaning “some” or “of the”.

Both are pronounced [dy], so the written accent helps readers know which word is intended.

Example:

• Il a dû partir. → He had to leave.
• Il a du pain. → He has some bread.

Without the accent, both sentences would contain du, which could be confusing. The circumflex in dû provides a clear distinction between a verb form and a partitive article.

In summary:

• du = contraction of de + le (article)
• dû = past participle of devoir (verb)

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Why Not the Others?

So why don’t we write eû, pû, vû, sû, or voulû?

The answer is that there’s no risk of confusion. These past participles do not resemble any articles or commonly used grammatical words, so they do not require an accent to distinguish them.

Examples:

• eu (had) does not resemble another word
• pu (been able to) is not confused with anything else
• vu (seen), su (known), and voulu (wanted) are equally unambiguous

Since there’s no orthographic confusion to avoid, no accent is needed.

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Feminine and Plural Forms of “Dû”

When the past participle dû agrees in gender and number with a preceding direct object, it takes standard participle endings. These forms also traditionally keep the circumflex, though modern usage varies.

Gender / Number	Form	Example
Masculine singular	dû	Il a dû partir. (He had to leave.)
Feminine singular	dûe	Elle l’a dûe. (She owed it.)
Masculine plural	dûs	Ils les ont dûs. (They owed them.)
Feminine plural	dûes	Elles les ont dûes. (They owed them.)

Although the traditional spelling includes the circumflex even in these longer forms, it is increasingly common in modern usage – especially in informal or digital contexts – to write due, dues, etc., without the accent, particularly since the circumflex can interfere with typesetting or digital character encoding.

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Summary: Why Only “Dû” Has a Circumflex

Word	Circumflex?	Reason for Use or Omission
dû	Yes	To distinguish from du (article)
eu	No	No similar-looking article to confuse it with
pu	No	No ambiguity
su	No	No ambiguity
vu	No	No ambiguity
voulu	No	No ambiguity