David is at the hospital waiting for his turn but he doesn’t have a watch.
David: Excuse me, sir, can you help me?
D: I have an appointment, but I am afraid I might be late.
D: At ten to eight on Monday morning.
C: You are not late, it is twenty to eight.
D: Great, I am ten minutes early.
C: Yes, we are open from 7 am to 7 pm.
D: Thanks sir.
C: You’re welcome.
External link to Aspects of time (Oral expression) exercises (1584).