You use the '-ing vorm' as a Noun
1. After Verbs that indicate 'start(begin)', 'end(eind)', or 'continuation (doorgaan)'. (start, begin, finish, go on, etc.)
Example: Everybody had finished writing.
2. After certain other verbs. (delay, postpone, put off, imagine, consider, avoid, etc)
Example: I put off learning vocabulary for a whole week.
3. After a few expression. (it's no good, it's no use, it's worth, can't help, to be busy, etc)
Example: She can't help singing all day long.
Leer al deze werkwoorden en uitdrukkingen op blz. 64 en 65 van je kleine boekje