Could anyone please tell me what differences the two words have when, say, one's talking about teachers?
Many thanks in advance.
I'm not a teacher :)
"skill" - is your ability, power or coordination of doing certain things by using your knowledge and experience - physically or mentally. For example: Being a teacher requires a lot of skill.
"expertise" - is an opinion/judgement/assessment given by an expert. For example: She can provide you with a legal expertise (meaning, she can present her professional opinion on legal matters).
Hope it helped,