The Dutch word for surgery is the cognate chirurgie - or operatie which is a cognate of operation.
Netherlands = Niederlande
Surgery.
Haarlem
It is spelled surgery.
sieraden
The letters spell the proper noun Holland (a region in the Netherlands, or a name for the country).
The spelling is operation (activity, or surgery).
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By learning to spell "their" correctly
The English name for the Dutch kingdom is "the Netherlands." The Dutch name is "Nederland."
The correct spelling of the brain surgery is "ventriculotomy".
Netherlands is 'les Pays-Bas' in French. In common conversation, they are most often referred to as 'la Hollande'.