A young couple alone in a car at night and nothing obscene is happening!

A cop was patrolling at night in a well known area for "parking."

He saw a couple in a car, with the interior light on. He got closer to the car and saw a young man behind the wheel, reading a computer magazine and a young woman on the rear seat, knitting.

Puzzled by this surprising situation, the cop walked over to the car and knocked on the window.
"Yes, officer?"

"What are you doing?"

"Well, isn't it obvious? I'm reading a magazine."

Pointing to the young woman, the cop asked, "And her, what is she doing?"

The young man shrugged, "I believe she's knitting a pullover."

The cop was totally confused. A young couple alone in a car at night and nothing obscene is happening!
"What's your age, young man?"

"I'm 22, sir."

"And her, what's her age?"

The young man looks at his watch and said, "She'll be 18 in 20 minutes. >=)