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Chain Composition

SYNTAX: process by which two independent chains, say (a₁,...,a_n) and (b₁,...,b_n), are linked to each other, thus forming one extended chain (a₁,...,a_n,b₁,...,b_n). Chain composition presumably takes place in a.o. parasitic gap constructions. Thus, in (i) there are two chains, (which gaps_i , t_i ), the result of wh-movement in the matrix clause, and (Op_j, t_j), resulting from movement of the empty Operator in the embedded adjunct clause. To give the parasitic gap in the embedded clause its correct interpretation (i.e. as a variable bound by which gaps), the chain headed by the Operator must be composed with the chain headed by which gaps.

(i) which gapsi did you hate ti [before [Opj [analyzing tj ]]]