Frisian exhibits the curious phenomenon of parasitic participles. one
occurrence of the perfect auxiliary is able to license more than one p
erfect participle. Recursive checking (a one-many relation) is possibl
e just in case the feature that recurs is not the one that is semantic
ally interpreted. Thus the feature on the perfect auxiliary is the one
that is semantically interpreted Central to our analysis is a relativ
ization of the head-movement constraint: movement of X across Y is ill
egitimate if Y possesses features relevant to X.