??????? (Wakarimashita ka.)
Do you understand?
????????? (Hai, wakarimashita.)
Yes, I understand.
?????? (Wakarimasen.)
I don't understand.
??????? (Itte kudasai.)
Please say it.
???????????? (Moo ichido itte kudasai.)
Please say it again.
??????? (Kiite kudasai.)
Please listen.
???????? (Kotaete kudasai.)
Please answer/respond.
??????? (Yoku dekimashita.)
Well done.
????????? (Ganbatte kudasai.)
Do your best, keep at it, keep trying! (encouragement)