boot stem
it is the third person plural of the present indicative, the very same as the stem for regular formation of the subjunctive (every stem besides nous and vous)
second stem
this is different than the boot stem and is used for nous and vous
aller
to go
boire
to drink
croire
to believe
devoir
to have to
mourir
to die
prendre
to take
recevoir
to receive
tenir
to hold
voir
to see
boot stem aller
j’aille
vouloir
to want