Here it is nicely illustrated:
Let's say a guy named Roger is attracted to a woman named Elaine. He asks her out to a movie; she accepts; they have a pretty good time. A few nights later he asks her out to dinner, and again they enjoy themselves. They continue to see each other regularly, and after a while neither one of them is seeing anybody else. And then, one evening when they're driving home, a thought occurs to Elaine, and, without really thinking, she says it aloud:' 'Do you realize that, as of tonight, we've been seeing each other for exactly six months?'' And then there is silence in the car. To Elaine, it seems like a very loud silence. She thinks to herself: Geez, I wonder if it bothers him that I said that. Maybe he's been feeling confined by our relationship; maybe he thinks I'm trying to push him into some kind of obligation that he doesn't want, or isn't sure of.
And Roger is thinking: Gosh. Six months.
And Elaine is thinking: But, hey, I'm not so sure I more...
Before he went off to the wars, King Arthur locked his lovely wife, Guinevere, into her chastity belt. Then he summoned his loyal friend and subject, Sir Lancelot.
"Lancelot, noble knight," said Arthur, "within this sturdy belt is imprisoned the virtue of my wife. The key to this chaste treasure I will entrust to only one man in the world. To you."
Humbled before this great honor, Lancelot knelt, received his king's blessing and took charge of the key. Arthur mounted his steed and rode off. Not half a mile from his castle, he heard hoofbeats behind him and turned to see Sir Lancelot riding hard to catch up with him. "What is amiss, my friend?" asked the king.
"My lord," gasped Lancelot, "you have given me the wrong key!"
In days of old, when knights were bold, this particular knight was leaving for a crusade and called of his squires: "I'm leaving for the crusade. Here is the key to my wife's chastity belt. If, in 10 years, I haven't returned, you may use the key."
The knight sets out on the dusty road, armored from head to toe, and takes one last look at his castle. He sees the squire rushing across the drawbridge, yelling, "Stop! Thank goodness I was able to catch you. This is the WRONG KEY."
Once upon a time an evil king captured a virgin princess and held her captive in his high tower. Though she was very beautiful he forced her to wear a disgusting and smelly burlap dress. "You'll never get away with this," she cried. "Some brave knight will rescue me!" "Not in that thing," the evil king replied. She waited day and night, but it was just as the king predicted. Every knight that saw her in the window of the high tower was scared away by her dress, which, as I've mentioned, was very disgusting. After many months the princess broke down crying and the evil king taunted her, "You see? I told you no knight would rescue a damsel in this dress!"
A knight and his men return to their castle after a long hard day of fighting."How are we faring?" asks the king."Sire," replies the knight, "I have been robbing and pillaging on your behalf all day, burning the towns of your enemies in the west.""What?!" shrieks the king. "I don't have any enemies to the west!""Oh, no..." says the knight. "Well, you do now."