French stem-changing verbs are conjugated with the same endings as regular -ER verbs but have two different radicals or stems. Stem-changing verbs are sometimes also called boot verbs or shoe verbs, because if you circle the forms that have stem changes in the conjugation table below, the resulting shape looks like a boot or shoe.
All verbs that end in -yer are stem-changing verbs, but there are two different varieties:
- Verbs that end in -ayer (see page 1) have an optional stem change
- Verbs that end in -oyer and -uyer (see below) have a required stem change
In the present tense, French verbs that end in -oyer and -uyer must change y to i in all forms but nous and vous.
-oyer verbs
je nettoie nous nettoyons
tu nettoies vous nettoyez
il nettoie ils nettoient
These stem changes are not limited to the present tense; see nettoyer in all tenses or the lesson on -yer verbs in other tenses.
Verb conjugation group
broyer - to grind
employer - to employ
envoyer - to send
nettoyer - to clean
se noyer - to drown
renvoyer - to fire
tutoyer - to use tu
vouvoyer - to use vous (learn about tu vs vous)
-uyer verbs
j' ennuie nous ennuyons
tu ennuies vous ennuyez
il ennuie ils ennuient
Verb conjugation group
appuyer - to lean, press
ennuyer - to bore
essuyer - to wipe
These stem changes are not limited to the present tense; see ennuyer in all tenses or the lesson on -yer verbs in other tenses.
Note: Verbs that end in -ayer have the same stem change, but it is optional: -ayer verbs.
