The study of passives has been instrumental to the development of modern linguistics, and passives are central non-canonical word order constructions (in the sense of Birner and Ward 1998) in most languages. However, while numerous cross-linguistic studies (e.g. Siewierska 1984, Shibatani 1985, Keenan 1985, Abraham 2006) have identified the core characteristics of passives, including demotion of the agent and promotion of the patient, there are passive constructions that exhibit behavior far from this norm. This dissertation examines a number of unusual characteristics of passive and related constructions, in particular in Mandarin Chinese and Taiwanese Southern Min, that challenge our common conception of passives. Chapter 2 investigates obligatorily agentive passives: corpus studies (e.g. Xiao et al. 2006) have found that agentive passives are more commonly used in Mandarin than in English, but more importantly, Mandarin and Taiwanese (and a few other languages) have passives that require the presence of the agent, departing from Keenan and Dryer's (2007) generalization that agentive passives must be able to manifest in the agentless form. Chapter 3 deals with completion entailment and passives: compared to English, Mandarin passives are more restricted by tense and aspect, but more interestingly, simple accomplishments in Mandarin do not entail a completive interpretation, however, when they are passivized, the completive interpretation becomes necessary. Chapter 4 explores adversity and passives: it discusses the close link of adversity to passives, and the question of why a marker used in a construction where the valence of a predicate is reduced is also often used in a construction where the valence of a predicate is increased. Syntactic and purely semantic approaches to passives cannot account for these behaviors; this dissertation proposes that an information structure approach, in particular along the lines of Birner and Ward (1998), can provide a more satisfactory account of these issues, and improve our understanding of the phenomenon of passivization. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]