The imperfect is very easy to form. You simply add –vo, -vi, -va, -vamo, -vate, -vano to the infinitive, after eliminating the –re from the infinitive. There are very few irregular forms of the imperfect; for example, -isc verbs are conjugated like all other –ire verbs (see finire below).
Following are examples from all three types of verbs:
amare—to love
(io) amavo (noi) amavamo
(tu) amavi (voi) amavate
(lui, lei, Lei) amava (loro) amavano
prendere—to take
(io) prendevo (noi) prendevamo
(tu) prendevi (voi) prendevate
(lui, lei, Lei) prendeva (loro) prendevano
finire—to finish
(io) finivo (noi) finivamo
(tu) finivi (voi) finivate
(lui, lei, Lei) finiva (loro) finivano
The verb avere is regular in the imperfect
(io) avevo (noi) avevamo
(tu) avevi (voi) avevate
(lui, lei, Lei) aveva (loro) avevano
Following are the most commonly used verbs that are irregular* in the imperfect:
* Notice that for all irregular verbs presented above (with the exception of essere), the only irregularity is found in an elongated stem. These stems come from the original Latin forms.