De or het bibliotheekvernieuwing?

The correct Dutch article is:

de bibliotheekvernieuwing

Rule Words ending in -ing: almost always de. See the rule

How to use bibliotheekvernieuwing

the bibliotheekvernieuwingde bibliotheekvernieuwing
this bibliotheekvernieuwingdeze bibliotheekvernieuwing
that bibliotheekvernieuwingdie bibliotheekvernieuwing
our bibliotheekvernieuwingonze bibliotheekvernieuwing
your bibliotheekvernieuwingjouw bibliotheekvernieuwing
every bibliotheekvernieuwingelke bibliotheekvernieuwing
which bibliotheekvernieuwing?welke bibliotheekvernieuwing?
a big bibliotheekvernieuwing / the big bibliotheekvernieuwingeen grote bibliotheekvernieuwing, de grote bibliotheekvernieuwing