Good morning teacher was marked wrong. I reported it Sept 14
I rather would say professor than teachet
So what is the difference between صَباح الخير and صَباح اَلْنّور
you say this to someone you meet in the morning صَباح الخير
that person answers this to your greeting صَباح اَلْنّور
It gets explained here: https://forum.duolingo.com/comment/34164941صَباح اَلْنّور is "bright morning" or "morning of light." Apparently it's a typical response to good morning,صَباح الخير.