Sluit het paneel stevig, wanneer u

Sluit het paneel stevig, wanneer u het hebt geopend.
Nadat u het paneel hebt geopend, moet u het helemaal sluiten.

Results (English) 1:

Close the panel firmly, when you have opened.
after you open the panel, you must close all the way.

Results (English) 2:

Close the Panel firmly, when you have it open.
After you have the Panel open, you must close it at all.

Results (English) 3:

Securely connect the panel, when you have opened it.
After you have opened the panel, you must close completely.