In the web, not in the up, Duolingo has grammar tips for every unit. I think they explain very nicely all those issues.
Can anyone tell me which ت is used before the ـها or the ـه , is it تَ or تِ or تُ because i notice its not consistent in another sentences and its confusing me
İt depends on the word and its role in the sentence,
İf it is منصوبة then تَ
İf it is مجرورة then تِ
İf it is مرفوعة then تُ
Could you explain how to know that its mansub, majrur or marfu? Because i am learning arabic only on duolingo