He only visits his parents once in a blue moon
This kind of opportunity comes along once in a blue moon
I used to go to the opera, but now I only go once in a blue moon
She was very busy, so we only saw her once in a blue moon
That restaurant is so expensive that we eat there once in a blue moon
We get snow in this region once in a blue moon
He's usually very serious, but once in a blue moon he'll tell a joke
The chances of winning the lottery are like seeing a blue moon
A total solar eclipse visible from this location happens once in a blue moon
This phenomenon occurs once in a blue moon, making it a rare sight
Did you see the shooting stars last night?
No, I missed them. I only see those once in a blue moon.
That is a shame. They were truly beautiful.
We only see them once in a blue moon
They appear extremely rarely
Such occasions are very infrequent