In negated sentences

The GB analysis of do-support in negated sentences hinges on the separation of the INFL and VP nodes (see [#!chomsky65!#], [#!jackendoff72!#] and [#!chomsky86!#]). The claim is that the presence of the negative morpheme blocks the main verb from getting tense from the INFL node, thereby forcing the addition of a verbal lexeme to carry the inflectional elements. If an auxiliary verb is present, then it carries tense, but if not, periphrastic or `dummy', do is required. This seems to indicate that do and other auxiliary verbs would not co-occur, and indeed this is the case (see sentences ((340))-((341))). Auxiliary do is allowed in English when no negative morpheme is present, but this usage is marked as emphatic. Emphatic do is also not allowed to co-occur with auxiliary verbs (sentences ((342))-((345))).

(339)0(339

(340)

$\ast$We will have do bought a sleeping bag .  (340)0(340

(341)

$\ast$We do will have bought a sleeping bag .  (341)0(341

(342)

You do have a backpack, don't you ?  (342)0(342

(343)

I do want to go !  (343)0(343

(344)

$\ast$You do can have a backpack, don't you ?  (344)0(344

(345)

$\ast$I did have had a backpack ! 

At present, the XTAG grammar does not have analyses for emphatic do. In the XTAG grammar, do is prevented from co-occurring with other auxiliary verbs by a requirement that it adjoin only onto main verbs (<mainv> = +). It has indicative mode, so no other auxiliaries can adjoin above it.^20.5 The lexical item not is only allowed to adjoin onto a non-indicative (and therefore non-tensed) verb. Since all matrix clauses must be indicative (or imperative), a negated sentence will fail unless an auxiliary verb, either do or another auxiliary, adjoins somewhere above the negative morpheme, not. In addition to forcing adjunction of an auxiliary, this analysis of not allows it freedom to move around in the auxiliaries, as seen in the sentences ((346))-((349)).

(345)0(345

(346)

John will have had a backpack .  (346)0(346

(347)

$\ast$John not will have had a backpack .  (347)0(347

(348)

John will not have had a backpack .  (348)0(348

(349)

John will have not had a backpack .