There are three major West Germanic languages: English, Dutch and German. The minor ones are Frisian and Afrikaans, the latter of which I believe is practically Dutch. People say Dutch has some features that may help speakers of North Germanic (Scandinavian) languages understand it.
I know English, Swedish and German because I studied them all in school. For me, Dutch has so many unfamiliar basic words that I'm quickly lost if I have to read even a simple Dutch language text.