1. anniversary
Thai Air celebrates its 50th anniversary this year.
Quite a few people have been invited to celebrate the couple's anniversary.
You are cordially invited to our fiftieth anniversary celebration.
Today we are celebrating the 6th anniversary of our entrance on the Chinese market.
wedding anniversary
She's pretending to be hurt because I forgot our anniversary.
Japan is marking the first anniversary of the devastating earthquake
Our company had the fortieth anniversary of its foundation.
One thing a married man should never forget is his wedding anniversary.
Today's ceremony marks the 100th anniversary of our school.
Today is my parents' 25th anniversary – it is exactly 25 years since their wedding.
The whole family was invited to a party to celebrate Ethel and James’s 25thwedding anniversary.
You forgot about our anniversary, how could you?
They celebrated their first wedding anniversary yesterday. The company celebrated its 50th anniversary.
It seems it was a gift for the 50th anniversary of Queen Elizabeth's accession to the throne.