In the main cities, you can get away with wearing pants or a skirt that reaches below the knee, and a short-sleeved t-shirt. The looser these are, the better, as they will serve you best in the heat of Morocco – plus, form-fitting clothing can be just as poorly received as exposed skin in certain areas.
Do men need to cover knees in Morocco?
No, you really don't have to do anything in Morocco when it comes to clothing. Yes, it is considered more respectable to cover up a bit more however there are no rules. My advice is to have options just in case you feel uncomfortable. More modest clothing is generally preferred in Morocco.