The Category P Features, Projections, Interpretation

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stranded. As already mentioned, movement upon P-stranding is typical of Caserelated
movement (compare with (63c)). 45
Thus the Op-chain in the PP is clearly not identical to the familiar A’-chain (e.g.
wh-movement). Its tail is a Caseless argument position, but its head is an A’-position
(spec of PP, see 5.4.2.3). 46
Recall that to is P pred , namely it does not have any φ-features, by assumption,
and therefore it cannot check structural Case at all. Consequently, the Op-chain in the
PP of object gap constructions is ‘Caseless’. A ‘Caseless’ chain is not visible at LF for
theta-assignment (i.e. the Case-marking on the head of a chain makes thetaassignment
possible at LF, Chomsky 1986, 1995). 47 Consequently, the internal thetarole
of the verb is not assigned to the Op-chain in the PP, but only passed on by it.
Since this role has not been assigned in the PP, it has to be externalized.
If P-to functioning as P pred can remove only Accusative, it follows that its
complement is invariably verbal:
(64) a. The book is easy to read
b. *The book is easy to reading
Since to does not remove the Genitive Case of the nominal (reading), and
assuming that the internal argument of the nominal is assigned to the Op, the Opchain
in (64b) is not Caseless, namely visible at LF and assigned the internal thetarole
of the nominal. Once the theta-role is assigned, it cannot be externalized.
That Accusative is indeed the only Case to removes is supported by the
following. A Dative verb like give can occur in English either in the Dative
construction (65a), or in the Double Object construction (DOC) (65b):
(65) a. Dan gave many presents to the children.
b. Dan gave the children many presents.
45 Be reminded that this should not be taken to imply that object gap constructions involve A-
movement, but rather that the Op-movement in these constructions is different from the regular whmovement.
For additional differences see Cinque 1990, Lasnik and Stowell 1991.
46 Cinque (1990) argues that instead of Op-movement, object gap constructions (and some related
constructions such as the parasitic gap construction) employ Op-binding of pro. Since pro is a
phonetically null nominal category, it can replace only DPs, but not PPs. Consequently, the fact that
only DPs can be Op-bound has nothing to do with Case under Cinque’s proposal (but see ahead).
47 The term ‘Caseless’ should not be taken literally. I simply use this familiar term to point out that the
A’-chain is ill-formed Case-wise.