The correct vowel endings damma, kasra, fatha in Arabic can be a headache. If you are careless, you could turn verse 9:3 of the Qur'an into blasphemy (kufr).
A final Aleph (ألف) in Arabic to express the accusative case (منصوب) can be tricky. Where do you put it on a final Hamza (همزة)? Here are the rules.