4 KudoZ points awarded for this answer. Comment: "Final rendering: Patients are not to leave their rooms without the permission of a physician. Discussion:May I refer you to the following link. http://homepage.mac.com/moogoonghwa/tsongkit/part2/II-7b-g.html#s17 Acknowledgement: I would like to thank both Anastasia and Last Hermit for their insightful entries. Certainly I could not have come up with my own without your help. I only regret that there was not more input from others, as well. Wherestip's own admission with regard to his knowledge of grammar, and Anastasia's unconvincing response, made Last Hermit's entry particularly attractive. Language patterns are not something that just occur; rather, they evolve based on already accepted patterns. The special use of 是。。的 confirmed by all contributors is not likely an accident. In addition, I have seen the phrases 不可以 and 不准 used in many contexts, both translated and untranslated, and they are often used synonymously. The latter appears to be a more formal written rendering of the former which is both spoken and written -- well, at least in Hong Kong . . . In any case, I am not convinced that I, myself, am right, but we are likely to encounter this same construction again further along, so that we might verify and elaborate. In the end, thank you everyone for making me think longer and harder. I am sure all users of Tsong Kit for Chinese Language Beginners -- including me -- will benefit. "