Is there any difference in expressing consent and assurance using adverbs "certainly" or "of course"? What would be more appropriate one in everyday conversation?
When it comes to expressing consent and assurance, I'd say the difference certainly isn't very big. :-) When faced with a question like
..."Of course" would probably be a more typical reply. But there's nothing wrong with "Certainly" either (although it might sound a little more formal).
Oh, as you mention the context is everyday conversation, you should also consider something like:
In this fashion,
When used for expressing agreement or giving permission in daily conversations,