difficult, hard
As professoras sabem lidar com crianças difíceis.
The teachers know how to deal with difficult children.
Todas as perguntas eram difíceis de responder.
All the questions were difficult to answer.
As frases do Tom são realmente difíceis de traduzir.
Tom's sentences are really difficult to translate.
Os últimos dias têm sido difíceis.
The last few days have been difficult.