Translation:Do you know anybody who drinks more coffee than him?
As per earlier exercises, "...than he" needs adding as it is correct English.
Reported, mentioning here for non-native English learners.
1) "...than he" is prescriptively correct English (just like in Polish; we're comparing subjects, not objects)
2) That said, "...than him" enjoys popular usage regardless and can be described as still descriptively correct, so should also remain in the database.
I'm a non-native English learner and made the same "mistake" notwithstanding. ;) And once again. Also reporting in hope for changes, may later learners fare better.
I believe that one is rejected because in that sentence 'coffee' is a direct object and as such would be put in the accusative case in Polish: "Znasz kogoś pijącego kawę więcej niż on?"
I'm not sure if "więcej" is wrong in your sentence, but "częściej" (more often) seems definitely safer to me if you choose such a word order.
You're right about the reason :)
It's because of the "drinking", you need "who drinks". "You know someone who drinks more coffee than him?" should work fine.
why is that when "do you know someone drinking more coffee than him" works fine...