"The personnel gets tired slowly."
Translation:Personalul obosește greu.
No idea how this sounds to Americans, but in several ways (word order, singular vs plural verb, use of term "The personnel") this just isn't a normal / natural sentence in British English. Re-phrasing it would really mean understanding what the author is trying to say / emphasize. The earlier debate seems to suggest that it's hard to know the best Romanian if the English is so unclear / unnatural.