The syntactic position of Polish <i>by</i> and Main Clause Phenomena
I show that the position of the irrealis particle <i>by</i> in Polish conditionals correlates with constraints on Main Clause Phenomena (MCP). When <i>by</i> is in C<sup>0</sup>, MCPs are precluded; when it is in a lower position, MCPs are available. I suggest that the movement of <i>by</i> to C<sup>0</sup> accompanies the A′-movement of a world operator in conditional clauses (Bhatt & Pancheva 2006). The operator movement acts as an intervener for MCPs (Haegeman 2007, 2010a, 2010b). I present evidence from MCPs such as contrastive <i>to</i>-topicalization, long extraction of adjuncts, speaker-oriented adverbs and the availability of correlativization. The different syntactic position of <i>by</i> is supported by evidence from the behavior of <i>wh</i>-pronoun-type vs. complementizer-type counterparts of <i>if</i>.