Questions & Answers about Мне не хватает времени на домашнее задание.
Мне is the dative case of я and literally means “to me / for me.”
In Russian, feelings like “lacking / having enough / needing” are often expressed with the person in the dative:
- Мне холодно. – It is cold to me → I’m cold.
- Мне нужно учиться. – It is necessary for me → I need to study.
- Мне не хватает времени. – Time is not enough for me → I don’t have enough time.
If you used я (nominative), it would sound like you are the grammatical subject doing an action, which is not how Russians normally structure this kind of idea. Here, the situation (time being insufficient) is what’s “happening to” you, so you’re in the dative: мне.