I go to school ON foot every day. Mistake: one should say ON foot, not BY foot
Yesterday, Paul went to work by car. Mistake: one should say BY car, not ON car
Kim's office on the fifth floor. Mistake: one should say ON the fifth floor, not AT the fifth floor
Kate is going to be late tonight. She's still at work. Mistake: one should say AT work, not IN work
They live on the outskirts of Madrid. Mistake: one should say ON THE outskirts, not AT outskirts
I met Alicia at the university. Mistake: one should say AT THE university, not ON university
