How to refer to university lecturers? Watch
Do you refer to them as Sir or Miss like it is done in school, or is it more like Mr/Mrs. Last Name or Professor Last Name?
I haven't come across any lecturers who would want to be called Sir/Miss.
If in doubt, refer to him by Dr./Prof. [surname] (this is generally considered the politest address) until you can ask them how they wish to be addressed. It won't offend them.