On the nominal structure of some clausal complements in Bulgarian. An experimental study of wh-extraction. За номиналната структура на някои подчинени допълнителни изречения в българския език. Експериментално изследване на екстракцията на въпросителни думи.

We explore the nominal structure of finite clausal complements of propositional attitude verbs in Bulgarian by examining potential complex NP island effects in wh-extraction out of these complements. A complex NP island structure is signaled by the presence of an overt correlative pronoun tova preceding the finite complement. We compared speakers’ judgments and reading patterns concerning wh-extraction out of complements preceded by overt correlative pronoun tova and those in which no overt correlative is present, in an acceptability judgment experiment using a factorial design. The experiment also included an online reading time task. We found that factors structure and dependency length affect acceptability of wh-dependencies with and without an overt correlative independently, but there was no additive effect. We conclude that both subtypes of clausal complements, with and without an overt correlative, are essentially island-like configurations, which supports the nominal structure hypothesis for Bulgarian. The reading time data also allowed us to track down interesting patterns of compatibility of different verbs with an overt correlative