Consider the following premises. For all y_1, y_1 is rich. John is reading a book if and only if Mary is rich. Can we infer the following from them? John is not reading a book.
 From the fact that for all y_1, y_1 is rich we can infer that Mary is rich. From the fact that John is reading a book if and only if Mary is rich we can infer that if Mary were rich, then John is reading a book. Finally, from the fact that if Mary were rich, then John is reading a book, and that Mary is rich we can infer that John is reading a book, which contradicts that John is not reading a book. Therefore, the answer is no.