amagaban
Imperfecto para el sujetoellos/ellas/ustedesdel verboamagar.

amagar

Ya era de noche, noche fría, sombría, con el cielo encapotado, cuyas nubes amagaban resolverse en nieve.
It was already night, cold and cheerless, the heavens being overcast with clouds which seemed to threaten snow.
Palabra del día
hervir a fuego lento