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 The head H of phase Ph may be assigned an EPP-feature.
The EPP feature is then held responsible for the intermediate steps in successive-cyclic movement (Chomsky’s indirectly feature-driven movement). As the accompanying text makes clear (p.108), Chomsky uses the term EPP feature as a cover term for φ-features, force, topic focus,. . . The features triggering movement, both terminal and intermediate steps, are therefore specific to the type of movement.
Chomsky has also acknowledged the need for parameterisation when he states that parammetrically varying properties of H enter into the application of [(i)].