Old French was the Romance dialect continuum spoken in territories corresponding roughly to the northern half of modern France and parts of Belgium and Switzerland from around 1000 to 1300. This extinct language was known at the time as the langue d'oïl to distinguish it from the langue d'oc (also then called Provençal) which bordered these areas to the south.
Old French verb is classified in weak and strong verbs. Weak verbs form two groups, one with verb infinitives ending in -er and another in -ir/-re. Strong verbs form three groups; the grouping is based on the perfect ending in Latin language (-i, -si, and -ui).