Hello. I'm Phil Murray with WORDS AND THEIR STORIES, a program in Special English.

"You do not need to be a rocket scientist." Americans hear these words often. People say them in schools, offices and factories. Broadcasters on radio and television use them.

This is how you might hear the words used.

Workers in an office are afraid to try to use their new computer system. Their employer tells them not to be foolish. "You do not need to be a rocket scientist to learn this," he says.

Or, high school students cannot seem to understand something their teacher is explaining. "Come on," she says. "You do not need to be a rocket scientist to understand this."

Or, a company that makes soap is trying to sell its product on television. "You do not need to be a rocket scientist to see that our soap cleans better," the company says.