The addressee honorification marker si-marked predicate in Korean must have an honorific vocative element in Spec-Voc in order for the unchecked feature of the addressee honorification marker si on Voc to be discharged in the Spec-head relation with the vocative element in Spec-Voc in the concept of Chomsky's (1995) Minimalist Program, which induces the addressee honorification at the speech level. The unchecked feature of the addressee honorification marker si-ess-upnita/sey-yo) percolates from T to Voc. At this point, VocP is above CP, which is why addressee honorification and impersonal subject honorification cannot appear in the embedded clause in Korean. Imperatives with quantificational subjects in English can exhibit, in addition to second person pronouns, third person pronouns as well. This is because a bound element exhibits either the person feature of the partitive phrase binding second or third person pronoun, or default third person value, which is against S. Park (2020).

We investigate the nature of the idiomatic gapped right dislocation constructions (RDCs), by examining the distinction between the idiomatic and non-idiomatic appendices. The overt idiomatic correlate in the antecedent clause plays a crucial role in identifying the idiomatic appendix of the gapped RDC. That is, the idiomatic appendix in the gapped RDC must hold the idiomatic correlate in the antecedent context. When the idiomatic appendix in the gapped RDC crosses islands such as a relative clause or an adjunct clause, the gapped RDC cannot preserve its idiomatic interpretation even when the verbal idiomatic expression is given in the antecedent clause or question. This is different from the fact that there is a parallelism between the plain gapped RDCs and the fragment answers, which shows a natural consequence under the standard assumption that the appendices and fragments are derived by ellipsis and are island-insensitive due to the repair effect. Hence, we follow the right dislocation approach for the idiomatic appendices in the gapped RDCs, which resolves the issue of the island sensitivity.

Why the negation movement rule that negation in the embedded clause may move to the higher clause cannot be applied to the Korean bi-clausal structure where the negative concord item (i.e., NCI) undergoes the so-called exceptional case marking (i.e., ECM) is because the ECMed element occupies some position in the matrix clause. When the so-called CP anaphora kulehkey ‘so’ replaces the embedded clause of the ECM construction, the ECMed NPI cannot be incorporated in it. These observations are in accordance with Lee's (2006) argument that the ECMed element is in a non-thematic argument position of the matrix clause (i.e., Spec of the matrix vP). Merchant's (2004) and Park's (2013) suggestions that the invisible negative head in fragment constructions can only appear in the matrix clause, but not in the embedded clause reveal the secret that there arises a grammatical contrast between fragment answers to an ECMed wh-question and a matrix question containing a wh-question in the embedded clause. The NCI fragment as a response to the ECMed wh-question is slightly degraded but acceptable, whereas the NCI fragment as a response to a matrix question containing other wh-questions in the embedded clause is considerably degraded and unacceptable.