When you visit the Netherlands, you'll probably be pleasantly surprised to find that a large number of people speak English very well. According to a study by the language instruction firm English First, people in the Netherlands were among the top five countries for English-speaking abilities as of 2011. That said though, it never hurts to speak some of the language when you visit another country, and the locals you meet in the Netherlands will probably appreciate your efforts.
To say a simple "hello" in Dutch, the language of the Netherlands, simply say "hallo." Going beyond that, you can say "good day" by saying "goededag," pronounced like "go-da-dog." For "good morning," say "goedemorgen," and for "good afternoon," say "goedemiddag," pronounced like "go-da-mid-dog." If you want to say "good evening," say "goedeavond," pronounced like "go-da-ahv-ond." If you make an attempt and you get it wrong, chances are the person with whom you're speaking will help to correct you to get it right. Speaking of greetings, don't be surprised if a Dutch person gives you kisses on the cheek when meeting you, or expects you to shake his hand when you make introductions.