No one responded because no one knew the answer. Only a copyright lawyer would know, and I am not one either but I’ll tell you what I do know.
Before Taiwan joined WTO, determining whether the work of a foreigner received copyright protection in Taiwan was very complicated and uncertain. It’s still not easy but since joining WTO, Taiwan is bound by the WTO’s TRIPS Agreement of 1994. Under the TRIPS Agreement, Taiwan must give the same protection to all other WTO members that it gives to its own nationals. It also must give the same protection to members of each WTO country that it gives to members of every other WTO country. In addition, the WTO requires Taiwan to give protection to the works of any citizen of a country that is party to a multilateral IP convention, including the Berne Convention on copyrights, pursuant to the terms of that convention. I believe the Berne Convention gives copyright protection as follows. Writing: life of the author plus 50 years; photos or art: 25 years from creation; music: 50 years from date recorded.
Among other things, the Berne Convention gives an author the exclusive right to reproduce or translate the work. Surely the Berne Convention contains a “fair use” exception but I dont know what it says. I doubt that it is 1/3 of the work (but maybe that’s a reasonable rule of thumb). Definitely, copying an entire book for your class is illegal if the book is protected. I guess you just need to use your best judgment.
In any event, I hope you will disregard wix99’s suggestion that students and teachers might as well violate the law and steal others’ property by illegally copying books because they illegally copy CDs and VCDs anyway. Ironlady, I’m glad that students in your school have learned the difference between right and wrong and refuse to steal when asked to do so by the professors. Hopefully that is a sign of a greater trend.