One sentence that uses the imperfect tense to tell what life was like when your grandparents were young is this:
Fireflies twinkled like tiny stars in the summer night, illuminating the dirt road that led to Grandpa's farm, where laughter and the smell of freshly baked bread always lingered in the air.
How to make sentences with the imperfect tense
The imperfect tense describes an action of the past that is not yet complete. Some other sentences that can be composed in this tense are;
Grandma's nimble fingers flew across the loom, weaving tales of forgotten heroes and magical creatures into vibrant tapestries that adorned the walls of their cozy cottage.
Music poured from battered record players in the evenings, filling the air with the sweet melodies of bygone eras, while the young lovers danced beneath the flickering kerosene lamps.