A feature-based analysis of PRO control

The analysis for obligatory control involves co-indexation of the control feature of the NP anchored by PRO to the control feature of the controller. A feature equation in the tree anchored by the control verb co-indexes the control feature of the controlling NP with the foot node of the tree. All sentential trees have a co-indexed control feature from the root S to the subject NP. When the tree containing the controller adjoins onto the complement clause tree containing the PRO, the features of the foot node of the auxiliary tree are unified with the bottom features of the root node of the complement clause tree containing the PRO. This leads to the control feature of the controller being co-indexed with the control feature of the PRO. Depending on the choice of the controlling verb, the control propagation paths in the auxiliary trees are different. In the case of subject control (as in sentence ((54))), the subject NP and the foot node are have co-indexed control features, while for object control (e.g. sentence ((53)), the object NP and the foot node are co-indexed for control. Among verbs that belong to the Tnx0Vnx1s2 family, i.e. verbs that take an NP object and a clausal complement, subject-control verbs form a distinct minority, promise being the only commonly used verb in this class. Consider the derivation of sentence ((54)). The auxiliary tree for persuade, shown in Figure 8.9, has the following feature equation ((58)).

(57)0(57

(58)

NP₁:<control> = S₂.t:<control>  

The auxiliary tree adjoins into the tree for leave, shown in Figure 8.10, which has the following feature equation ((59)).

(58)0(58

(59)

S_r.b:<control> = NP₀.t:<control> 

Since the adjunction takes place at the root node (S_r) of the leave tree, after unification, NP₁ of the persuade tree and NP₀ of the leave tree share a control feature. The resulting derived and derivation trees are shown in Figures 8.11 and 8.12.

{Tree for persuaded

 

{Tree for leave

 

{Derived tree for Srini persuaded Mickey to leave

 

{Derivation tree for Srini persuaded Mickey to leave