1 On tough-movement* Milan Rezac, University ... - Multimania.co.uk

Although there is reason to be cautions, there is evidence that the TM gap behaves like a null
pronoun rather than an Ā-trace/copy. The location of the gap is constrained by the locality of Ā-
Agree, so this pronoun enters into pure Ā-Agree with C OP , without any displacement consequent
on this relation itself. I assume that the pronoun has an Ā-feature that renders it active for the Ā-
system, so I will refer to it as pro Ā ,
Pro Ā requires Agree to eliminate its Ā-feature. The C OP head of OP clauses, which has an Ā-
probe, considers pro Ā a match and Agree between the two satisfies the requirements of both.
Following Brody (1993:8f.), I have been assuming that C OP (like e.g. C Q ) is subject to selection,
accounting for why impossible but not (not) possible is a TM trigger. Three related questions
arise: (i) whether are there non-arbitrary restrictions on the selection of C OP ; (ii) why does C OP
require pro Ā and is not content with e.g. a relative pronoun; (iii), and vice versa, why is pro Ā
limited to clauses with C OP and does not appear in clauses that have a suitable Ā-probe provided
the semantics does not require that the Ā-probe have another goal, for example why can pro Ā not
appear in a regular clause under topicalization. Some inroad on answering these seems possible.
Consider the general class of "On wh-movement constructions" in English (Chomsky 1977,
Browning 1989). Wh-questions and topicalizations, which may be finite or non-finite, necessarily
have an overt goal for their Ā-relation which moves to their left periphery, (63). Let's set these
aside from those whose left periphery need not be overtly filled by the Ā-goal.
(63) I don't know what/*∅ (I want) to bake.
Among the rest, there is a split between those whose topmost clause must be tensed, namely
tensed relatives, clefts, and comparatives, and those where it must be infinitival, namely
infinitival relatives, tough-movement OP clauses, degree clauses, and purpose clauses; parasitic
gaps are possible with both infinitival and tensed clauses (Culicover 2001). Browning
(1989:127ff.) views tense as significant. Only the tensed group may have overt an Ā-phrase,
deletable up to recoverability (Chomsky and Lasnik 1977), (64), while the infinitival group must
use "null operators" (with one exception, below), (65). Levin (1983, 1984) develops an attractive
explanation for this: overt Ā-phrases require Case(-like) licensing, which a tensed but not an
infinitival T provides to its local [Spec, CP]. It is also only the tensed group, setting aside
parasitic gaps, which shows relative insensitivity to depth of embedding, intervening tensed
clauses, and subject/object asymmetries (aside from that-trace). One could take degradation in
these contexts to arise from the null nature of this group's Ā-phrase. However, as Browning
(1989:144f.) observes, infinitival relatives do in fact allow overt operators, provided they piedpipe
other material, (66). 29
(64) Overt operator in tensed constructions
a. the dragon who talked with Ath
b. John has more money than what I have. (Browning 1989:127)
(65) Overt operator in TM
a. Wade and Guingelot are easy/too mysterious (*who) to talk about at length.
b. *Wade and Guingelot are easy/too mysterious about whom to talk at length.
(66) Overt operator in infinitival relatives
a. A person *(who) to invite. (Browning 1989:127)
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