sentences:  In (a), the adverb "dake" is clearly attached to C; so even in the complementizerless environment (b), the adverb "dake" must still attach to C, thus pointing to the existence of a null complementizer in this phrase.The IP Hypothesis, on the other hand, asserts that the complementizer layer is simply nonexistent in overtly complementizerless clauses.Literature arguing for this hypothesis is based upon the fact that there are some syntactic environments under which a null C head would violate the rules of government under the Empty Category Principle, and thus should be disallowed.