Ik doe de deur open.
Ik wil opendoen.
Ik heb opengedaan.
I open the door.
Yes. opendoen splits into open + doen. In a main clause the prefix goes to the end: Ik doe de deur open.
The perfect tense is "Ik heb opengedaan" — the -ge- slots between the prefix and the stem.
opendoen means "to open (the door)". Example: Ik doe de deur open. (I open the door.)
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