De or het langetermijnlening?

The correct Dutch article is:

de langetermijnlening

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

How to use langetermijnlening

the langetermijnleningde langetermijnlening
this langetermijnleningdeze langetermijnlening
that langetermijnleningdie langetermijnlening
our langetermijnleningonze langetermijnlening
your langetermijnleningjouw langetermijnlening
every langetermijnleningelke langetermijnlening
which langetermijnlening?welke langetermijnlening?
a big langetermijnlening / the big langetermijnleningeen grote langetermijnlening, de grote langetermijnlening