范文：

　　The professor talks about two strategies that are used in TV ads that will make them more convincing. One strategy is repetition, when people hear something often enough, the message becomes positive. Take a car ad for example, the narrator says “plenty of room for everyone” for many times, although the car is small, eventually people will start to think that the car is fairly big. The second strategy is using a celebrity to advertise a product because people tend to believe someone famous. A race car driver who says “I like my car fast!” might actually make people think the car in the ad to be pretty fast, because we find them trustworthy.