It is a very common phenomenon for us when we go shopping ,we will buy what we need in daily life toghter with many "free" plastic bags ,which we are inclined to discard casually.It is an intresting and" beautifull landscapes" to see many corlorfull plastic bags flying in the sky especially when there is a strong wind.And we call these plastic bags "white pollution".As we all know,the white pollution is besoming more and more serious nowadays.Though we know its bad effects,still we find it difficult to refuse them,as they are very convenient for us.For instance,if we set a plastic bag into a bowl when we eat our foods,we will feel it easy to wash.However we ignore its bad effects.So,I think,we should keep a careful eye on them to keep our healthy and have a beautiful environment.