Consider the following premises. Thomas is not curious. For all y_3, if y_3 works, then y_3 is writing a letter. For all y_3, if y_3 writes a letter, then y_3 is working. Linda is writing a letter if and only if Thomas is curious. Can we infer the following from them? Linda is not working.
 From the fact that for all y_3, if y_3 works, then y_3 is writing a letter, and that for all y_3, if y_3 writes a letter, then y_3 is working we can infer that for all y_3, y_3 will work if and only if y_3 will write a letter. From the fact that for all y_3, y_3 will work if and only if y_3 will write a letter we can infer that Linda is working if and only if Linda is writing a letter. From the fact that Linda is writing a letter if and only if Thomas is curious, and that Thomas is not curious we can infer that Linda is not writing a letter. Finally, from the fact that Linda is working if and only if Linda is writing a letter, and that Linda is not writing a letter we can infer that Linda is not working. Therefore, the answer is yes.