英语幽默:时态

The teacher says: Today, we're going to talk about the tenses. Now, if I say "I am beautiful," which tense is it?

The student says: Obviously it's the past tense.

NOTES:
Present Tense: I am beautiful.
Past Tense: I was beautiful.
This is funny because the teacher isn't beautiful now, but maybe she was beautiful when she was younger.