I am sorry I am so late to work.
What was the problem?
I lost track of time.
Things happen ; make sure it doesn't become a habit.
OK, it won't happen again.
All right, please take this message and call this client.
OK, no problem.
Now does everyone understand the diagram on the board?
Yes, I understand the numbers.
I will explain it again ; especially for those of you who arrived late.