"Have to" and "should" I want to know the deference between "have to" and "should". Today, a foreigner asked to me in the train. She said "We want to go here( she had a map). How can I we there?" This is my first time to be asked the way from foreigners. So my brain didn't work soon. I said "you HAVE TO change the train!!" She said "Thank you" But after that short conversation, I wondered "HAVE TO " is strict to say in that case??? Hmmmm I don't know... Please tell me what I have to? Should? Say her!

How can I say that...? How can I say "そんなことないよ" in English... For example... A: you are very smart!! B: ( ? ) ↑ そんなことないよ Like this... How do you say that??