Las pinturas y las lámparas se movían y yo gritaba.en: The paintings and lamps were moving, and I was screaming.
Duolingo forum topic: https://forum.duolingo.com/comment/46527948
i find the use of the imperfect for gritar a bit surprising. I would expect the preterite, as it would seem to be something that would happen, and presumably be complete as he fled
Depends on the nuance you want to impart. If you mean to focus on the idea that in that specific moment you screamed then yes you could say:
Las pinturas y las lámparas se movían y [en ese momento,] yo grité
But the sentance as given works in the sense of describing various things that were happening concurrently: 'the pictures were moving + the lamps were moving + I was screaming...'
You could imagine adding other things to the list as well: 'the doors were creaking, the curtains were billowing, chains were rattling, your friends were running away' etc so that the fact of your screaming is just one of the things happening within a dramatic moment you are describing.
In which case imperfect works better
Pretty big difference between 'I was screaming' and 'I screamed'.