Basic English Conversation

Using "I am in/at/on"
Using I am in;
I am in the shower.
I am in the class.
i am in the School.
I am in University.
Using I am at;
I am at the Grocery.
I am at the mall.
I am at the Airport.
I am at the Hospital.
Using the word "on"
I am on the Table.
I am on a Bus