difficult
US /ˈdɪf.ə.kəlt/
UK /ˈdɪf.ə.kəlt/

1.
difficile, ardu
needing much effort or skill to accomplish, deal with, or understand.
:
•
The exam questions were very difficult.
Les questions de l'examen étaient très difficiles.
•
It's a difficult decision to make.
C'est une décision difficile à prendre.
2.
problématique, épineux
full of problems; problematic.
:
•
They are going through a very difficult period.
Ils traversent une période très difficile.
•
He has a difficult personality.
Il a une personnalité difficile.