书面表达假如昨天你在公共汽车上看见一个年轻人给一个抱小孩的妇女让座,但那个妇女并为表示感谢.请你用英语写一篇短文介绍一下

Bues are always crowded in rush hours.Students and office workers go to work or go back homeat that time.There are often full of people and one can hard to get a seat.And so does today.A mother with a kid is in the bus.An old adult offer a seat for her.But the young ignore her.
As the youths,I think it's necessary for us to offer seats for those who really need them,such as expectant mothers,disabled people ,old people and so on.
First,it's the behavior of good manners.You are polite enough if you do so.Second,it's the need of social morality.
However,if you can't achieve this,you are probably a definit person.And as a result,you can't be trust in the social activities.
So,let's build a good social order from offering a seats,just from you and me.