How to Conjugate "Mentir" (to Lie) in French

A Quick Lesson in Basic Verb Conjugations

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The French verb mentir means "to lie." While that may be relatively easy to remember, you'll also want to know how to conjugate the verb. This will allow you to use it appropriately in the present, past, or future tense and form a complete sentence. Mentir is not the easiest conjugation, but this lesson will walk you through the most basic forms you need to know.

Basic Conjugations of Mentir

Mentir is an irregular verb, which is what makes its conjugations a little more challenging than others.

It doesn't follow a regular pattern in the infinitive endings, though most French verbs ending in -mir, -tir, or -vir are conjugated in the same way. You might find it helpful to study a few at once to make memorizing each a little easier.

The imperative verb mood is used most often and allows you to express mentir in the present, future, and imperfect past tenses. Since it is irregular, you will notice that the verb stem—men- —has some unusual endings in this chart. However, with enough practice, you can commit them to memory.

Using the chart, match the subject pronoun to the appropriate tense for your sentence to find the correct conjugation. For example, "I am lying" is je mens and "we lied" is nous mentions.

 PresentFutureImperfect
jemensmentiraimentais
tumensmentirasmentais
ilmentmentiramentait
nousmentonsmentironsmentions
vousmentezmentirezmentiez
ilsmententmentirontmentaient

The Present Participle of Mentir

The present participle of mentir is produced by adding -ant to the verb stem.

This gives you the word mentant.

Mentir in the Compound Past Tense

In French, the passé composé is a compound past tense. It is constructed by combining a present tense conjugate of the auxiliary verb avoir with the past participle menti. For example, "I lied" is j'ai menti and "we lied" is nous avons menti.

More Simple Conjugations of Mentir

Beyond those basic conjugations, you may find yourself needing a few other forms of mentir at times. These can be rather useful if, for instance, the action of lying is uncertain, in which case you'll use the subjunctive. Or, the lying may depend on something else, so the conditional can be used.

On occasion, you may also encounter the passé simple or the imperfect subjunctive. Yet, these are rarely used so they do not have to be a priority in your studies.

 SubjunctiveConditionalPassé SimpleImperfect Subjunctive
jementementiraismentismentisse
tumentesmentiraismentismentisses
ilmentementiraitmentitmentît
nousmentionsmentirionsmentîmesmentissions
vousmentiezmentiriezmentîtesmentissiez
ilsmententmentiraientmentirentmentissent

With mentir you will find the imperative form useful for short commands. When using it, skip the subject pronoun: use mens rather than tu mens.

 Imperative
(tu)mens
(nous) mentons
(vous)mentez