Wug test

wug test, in linguistics, a test of the progress of the development of the allomorphs of the plural morpheme in children acquiring English.

The child is presented with some sort of pretend creature, and told, "This is a wug." Another one is shown. "Now there are two of them. There are two...?" Children who have successfully acquired the allomorph /z/ of the plural morpheme can respond: wugs /wVgz/ (see SAMPA for phonetic symbol key).

There are three plural allomorphs in English: /z/, the most general form (dogs, /dAgz/; /s/, which appears after voiceless consonants (cats /k}ts/); and /@z/, which appears after sibilants (horses, /hOrs@z/).

Preschoolers aged 4 to 5 tested best in dealing with /s/ and /z/ after a voiced consonant; less well in dealing with /z/ in other environments such as after nasals, rhotics, and vowels. However, children in grade 1 were almost fully competent with both /s/ and /z/.

Both preschool and first-grade children dealt poorly with /@z/, giving the correct answer less than half the time, possibly because it occurs in the most restrictive context.

The original wug test was done by J. Berko and is reported in her article "The Child's Learning of English Morphology," Word 14:150-77 (1958).