Saya punya pertanyaan. Kalo bilang "Dia punya pengacara itu orang jahat." artinya lain ya?
In some regional dialects that's fine. In formal Indonesian, your sentence roughly translates to he has a lawyer that's a bad person, and unclear which one is the bad person
"Pengacaranya adalah seorang jahat." should also be accepted
"Seorang jahat" is just "a bad" with jahat takes the place of subject, not adjective
Needs "yang" to attribute "bad" to "person"
Pengacara dia ada seorang yang jahat. What's wrong, please?
Is the literal translation to English - His lawyer is a person that's bad? Yang means that, right?
Yep, your sentence would be the literal translation.
What's the difference between ada and adalah?
"ada" can have three meanings:
-there is/are (ada buku di meja)
-to be at a place (dia ada di jakarta)
-to have something (saya ada kelas kemarin)
"adalah" most similarly translates to "to be" aside from the case above
pengacaranya adalah orang yang nakal not accepted