お元気の由、何よりです。
I am very glad to hear that you are well.
ご結婚なさった由、心よりお祝い申し上げます。
I hear that you have married, and I offer my heartfelt congratulations.
先生は来月退院される由です。
I am told that the teacher will leave the hospital next month.
この由を皆様にお伝えください。
Please convey this to everyone.