title: The acquisition of the present perfect: explaining differences in the speech of Scottish and American children.
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007802:Language; D007804:Language Development; D008297:Male; D011578:Psycholinguistics; D012606:Scotland; D012660:Semantics; D014481:United States