ils volaient

were flying, were stealing

→ voler
vol to fly + aient they were ...ing (imperfect past)
verb · third plural · imperfect indicative Rare #38,399
were flying
FR: Les oiseaux volaient au-dessus du lac.
EN: The birds were flying above the lake.
were stealing
FR: Ils volaient des vélos la nuit.
EN: They were stealing bikes at night.
Conjugation of voler
Indicative imperfect
SingularPlural
Third volait volaient

Ce jour-là, des drapeaux japonais volaient au vent.

That day, Japanese flags were flying in the wind.

Et si les garçons volaient l'argent?

What if the boys stole the money?

— Masaan (2015)

Ils faisaient le poirier, volaient sur le dos et faisaient du vélo.

They did handstands, flew on their backs and rode bicycles.

— Apocalypse Now (1979)

Les mouettes volaient sur la mer.

The seagulls were flying over the sea.

Les oiseaux volaient en formation.

The birds flew in formation.