Meer Uitgebreid Lager Onderwijs (Dutch, "more advanced primary education") was during part of the twentieth century a level of education in the Netherlands (and the Dutch East Indies), comparable with the junior high school level in the US education system. Its successors were the mavo and vbo, now both replaced by vmbo.
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Meer Uitgebreid Lager Onderwijs Wikipedia(Text) CC BY-SA