amistaron
Pretérito para el sujeto ellos/ellas/ustedes del verbo amistar.

amistar

Previamente ellos habían sido enemigos, pero ahora se amistaron.
They had previously been enemies, but then they were made friends.
Se conocieron en la universidad y allá se amistaron para siempre.
They met in college and there they became friends for ever.
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