
 Originally Posted by 
Полуношник        
 Originally Posted by 
scotcher   You're right. The problem is that to express the Russian sentence in English properly you need to use a different sentence structure, because the direct translation, "The doctors diagnosed him for a long time", isn't idiomatic English.
 
I would say "The doctors spent a long time diagnosing him." is the closest you can get.
      The sentence isn't correct in Russian either. Диагностируют 
болезнь, а не пациента.
       Fair enough, but couldn't 
его refer to a (masculine) illness? 
грипп, or 
рак, for example? 
In which case the English translation would be something like "The doctors spent a long time diagnosing it".