英语说明文：介绍一种物品.10月21日要

As we all know,TV is an important assistant in our dailiy life.Not only can we watch all kinds of programes from it,but also we can learn much knowledge by watching TV.It is a technical device playing an imprtant role in our entertainment time .TV has experienced a long development period from black-and-white to colorful nowadays .It is a witness of times.As to our sudents,we should prevent ourselves from being addicted to TV,but some attention paid to it is still needed.