  According to another school of thought, however, the language  abilities of WS subjects might be more normal than those of Downs  syndrome individuals, and might look remarkable in contrast to their  own marked disabilities in other areas, but nonetheless display a  number of abnormal characteristics across a variety of measures when  investigated further. WS language shows “massively  delayed” early acquisition, especially of vocabulary (Bellugi  et al. 2000:11) and grammatical morphemes (Caprirci et al. 1996); overregularization of regular plural and past tense endings as well defective competence with regard to irregular nouns and verbs (Clahsen and Almazan 2001); “inordinate difficulty with morphosyntax” (Morris and Mervis 2000: 467; see also Volterra et al. 1996; Karmiloff-Smith et al. 1997; Levy and Hermon 2003); and impaired mastery of relative clause constructions (Grant et al., 2002), embedded sentences, and (in French) grammatical gender assignment (Karmiloff-Smith et al. 1997). Indeed, Bellugi et al., 2000, found that WS children's performance on a sentence-repetition task was indistinguishable from that of matched controls diagnosed with Specific Language Impariment, or SLI (see below, §3.6.2). Findings such as these lead experts such as Annette Karmilloff-Smith to urge “dethroning the myth” of WS' “intact” syntactic abilities (Karmiloff-Smith et al. 2003) and move Ursula Bellugi — formerly a proponent of the ‘spared language’ viewpoint — to caution that “because their language abilities are often at a level that is higher than their overall cognitive abilities, individuals with WMS might be perceived to be more capable than they really are.” (Bellugi et al. 1999.)