to criticize someone unfairly; to speak badly about someone
criticar a alguien injustamente; hablar mal de alguien (kritikhar a alguien injustamente; hablar mal de alguien)
"He always runs his coworkers down behind their backs."
"Él siempre habla mal de sus compañeros a sus espaldas." (El siempre corre a sus compañeros hacia abajo a sus espaldas.)
to start working hard on something
an attempt to deceive someone into revealing personal or con...
to start working seriously
very calm and composed
to stay focused on your goal despite difficulties
not very intelligent