英语翻译You cannot appreciate happiness unless you have known sa

英语翻译You cannot appreciate happiness unless you have known sadness too.I've hurted somebody for I thoughe she or he would stay by my side forever.But now I just find that I am wrong.For everybody,no one will trully be his companion forever.As time goes by,everything is changing too,especially many people.Time is a strong fiood,we needn't do anything.Time can also change the most important thing to you.So,I will never think about what will happen to me in more than 1 year.What I most concern is:love the persons who really love me.Don't cry because it is over.Smile because it happened.