"当你看电影时，女主角总是漂亮而苗条。总有一个女生比较胖，他们总是让她扮演一个被戏弄的角色。"

Simplified Meaning:

A lot of movies like to show the main female character as very pretty and slim. They often put a bigger girl in the background and make jokes about her size. This isn't fair because it sends a message that only thin girls can be the main star and be admired. It also hurts the feelings of people who don't fit that image because they see themselves being laughed at. For example, if you think about high school movies, the popular girl is almost always the thin, pretty one who everyone wants to be friends with. The bigger girl, if she's there, is often the funny sidekick or the one everyone makes fun of. This can make people believe that to be important or loved, you have to look a certain way, which isn't true. To change this, filmmakers need to show women of all shapes and sizes in important roles without making jokes about their looks. This way, everyone watching can feel seen and valuable just the way they are. If we respect all body types in movies, it can help people learn to respect and accept themselves and others in real life too.