Once in a Blue Moon

 Hey everyone!
Winter is coming and so the nights are getting longer.
Here is our phrase for today "Once in a blue moon"

We use this phrase to refer something that rarely happens or not very often.
This is because blue moons are a very rare event!

For example:
"My sister lives in Alaska, so we only see her once in a blue moon"
"He will only admit he is wrong once in a blue moon!"
Once in a blue moonとは、『めったにない』や『ごくまれに』という意味です。