Principal: Are you chewing gum?
Student: No, I am human being.
Wife: We are having mother for dinner tonight.
Husband: Make sure she is well cooked.
Father: Shameful results. Do you always get such low marks?
Son: No, only when I give exams.
Guest: Will these stairs take me to the second floor?
Boy: No, you'll have to walk as well.
Girl: I have changed my mind.
Boy: Thank God! Does the new one work?