先翻译成白话：

白发虽然不能代表什么，但我已经老了。青春过去不再回来，你知道吗？ 当你年龄过了二十就不再是小孩子了。到那时如果还是无所作为，仍旧学不成，名不就的的话，这不是枉为一个大丈夫嘛（只有学有所成，才能称得上大丈夫）。

再翻译成英语：

Although white hair can not symbolize anything except being senile.Have you known that youth in the past can no longer come back?You will be no longer a child when you arrive at twenty years old.At that time,only you have obtained excellent achievement in your study,you can be called a true man.