The 2017 FIFA U-20 World Cup was the 21st edition of the FIFA U-20 World Cup, the biennial international men's youth football championship contested by the under-20 national teams of the member associations of FIFA, since its inception in 1977 as the FIFA World Youth Championship. The tournament was hosted by South Korea between 20 May and 11 June 2017.

Can we draw the following conclusion?
The 2017 FIFA U-20 World Cup occurs every two years.
Yes