作文4

 Analyse of  a public service ad

      In the bottom of the picture,there is an image of a people's brain and a line of words"Brain Injury Association of America",therefore,we can know that the ad is made by such an association and the main idea of the ad is about safety.

      Then let's look at the mid of the ad,the words"Until the world is this safe,wear a helmet" tell us that this ad is aimed at  reminding cyclists of the significance of wearing helmets.The ad uses a large pair of quilt as the main illustration,in the middle of which is only a cyclist who is riding a bike without wearing helmet. Firstly,the quilt is of close shot,while the cylist is of prospect shot.Then the ad can convey the message to audience that the cyclist is riding in the safe area surrounded by the quilt.What's more,here we can spot a metaphor used in the ad,a pair of quilt makes people feel comfortable and safe,so the quilt can be compared to a safe world cyclists are riding on.Actually,the world is not as safe as the quilt,the quilt's ideal,clclist is real,so it's important for cyclists to wear helmets while riding bike,just like the message tell us.Last but not least,the cyclist is in oblique angle,which allows us to see the cyclist completely as well as makes audience feel that the cyclist is riding freely and smartly in the vast area.