has been complicating
-ha estado complicando
Presente perfecto progresivo para el sujetohe/shedel verbocomplicate.

complicate

If this were so, we would discover a great misunderstanding which has been complicating things up until now.
Si esto fuera así, descubriríamos un gran malentendido que ha complicado las cosas hasta nuestros días.
Palabra del día
la cometa