IMPERFECT INDICATIVE: USES
1) The imperfect indicative tense is expressed in English by
a) the past tense;
b) "used to" / "would" + verb;
c) "was" / "were" + present participle.
1
2) The imperfect indicative describes or expresses an action or state of being in the past.
a) Since the word imperfect means "incomplete," the imperfect tense
(unlike the preterite) does not take into consideration the beginning, end, or
definite time limit of the action or state of being.
b) What the imperfect describes may provide background information and/or
set the scene (= time, weather, etc.) for another action or state of being
(expressed in either the imperfect or the preterite).
Quando cheguei, era meia-noite e chovia.
(arrived // was / was raining)
Quando elas eram jovens, iam a Lisboa.
(were // used to / would go)
3) The imperfect indicative also expresses
a) two concurrent actions or states of being, one of which is often introduced by
enquanto ("while"):
Enquanto ele lia, eu dormia.
(was reading / was sleeping)
b) a continuing, habitual, routine, recurring, or indefinitely repeated action,
and is often used with these adverbs:
algumas vezes // às / muitas vezes
(sometimes // at / many times)
todas as semanas // todos os dias / meses / anos
(every week // day / month / year)
antes / antigamente / no passado
(before / formerly / in the past)
Antigamente Gilberto morava no Brasil.
Às vezes os seus pais viajavam a Moçambique?
No passado nós líamos pouco, mas eles liam todos os dias.
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1
This construction more commonly expresses the Portuguese imperfect "progressive" tense
(see p. 212 for details).
2
When used with the preterite, sempre connotes a definite time limit (e.g., "from beginning to end").