This is because wug [wʌg] was one such pseudoword used by Jean Berko Gleason in her wug test 1958 experiments.[5] Words like wug, which could have been a perfectly acceptable word in English but is not due to an accidental gap, were presented to children. The experimenter would then prompt the children to create a plural for wug, which was almost invariably wugs [wʌgz]. The experiments were designed to see if English morphophonemics would be applied by children to novel words.