6. We exchange New Year’s cards just as you exchange Christmas cards.
日本人は年賀状を出しますが、それはクリスマスカードのようなものです。
⇒ Christmas cards are supposed to arrive before Christmas as where New Year’s cards are supposed to arrive on New Year’s Day.
If you get a New Year’s card from someone you didn’t send one to, it’s considered good manners to send one back with a short note on it