My name is Tiago and I'm an English teacher in Brazil.
I want to clear up a doubt, will you help me?
What's the difference between:
I am in the restaurant.
I am at the restaurant. If I am "in the restaurant", I am inside (within the confines) of the restaurant. If I am "at the restaurant", I may be outside the restaurant. Both could be used to indicate that you are inside the restaurant, but only "at the restaurant" could mean that you are somewhat near the restaurant.
and why do we say:
I am in the chair.
I am on the sofa.
There is no real sense to how these words are used. Even worse, "I am in the chair" if I am sitting back, but I am "on the chair" if I am sitting on the edge of the seat. An engine is "in the bus", but a passenger is "on the bus". Passengers are "in a car" but "on a bus". The only way that people seem to learn the distinction, or, the rule (if one exists) is through being exposed to the language.
thanks for your attention!