has been slacking
-ha estado holgazaneando
Presente perfecto progresivo para el sujeto he/she del verbo slack.

slack

Ever since he brought in his friend Steph to the company, he has been slacking and his work has been unsatisfactory.
Desde que trajo a su amigo Steph a la compañía, ha estado decayendo y su trabajo ha sido insatisfactorio.
Palabra del día
saborear