De or het goodwillmissie?

The correct Dutch article is:

de goodwillmissie

Rule Words ending in -tie and -sie: almost always de. See the rule

How to use goodwillmissie

the goodwillmissiede goodwillmissie
this goodwillmissiedeze goodwillmissie
that goodwillmissiedie goodwillmissie
our goodwillmissieonze goodwillmissie
your goodwillmissiejouw goodwillmissie
every goodwillmissieelke goodwillmissie
which goodwillmissie?welke goodwillmissie?
a big goodwillmissie / the big goodwillmissieeen grote goodwillmissie, de grote goodwillmissie