This might be a little overkill for an airsoft event, but here are a couple guidlines for people playing as Dutch civilians during events/games/displays.
There are also sections for the Axis or Allies.
These were setup by Joeri, also known as Miss Marloes on several Re-enactment Forums.
http://www.nederland4045.nl/richtlijnen/uk.htm
Are there any particular phrases you would like to have in Dutch?
Wikipedia has a nice selection of Dutch Phrases with phonetic explanations:
http://wikitravel.org/en/Dutch_phrasebook#Basics
"OZO!" was a much heard phrase and seen as grafitti in later part of the war. It stood for "Orange shall overcome" or "Victory shall belong to Orange". The Germans had no idea what it meant and figured it was some kind of greating and started using it too.
"Mof", The Dutch version of "Kraut" or "Jerry". Originally refers to the way German Language sounds to the Dutch: Grumpy.
That's all I've got time for today! Next lessen tomorrow, if Silent Hunter IV doesn't get in the way 
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