Consider the following premises. For all x_14, if x_14 were an electrician, then x_14 is a police officer. If William were a police officer, then David is writing a letter. If it is sunny, then William is a police officer. It is sunny or William is an electrician. Can we infer the following from them? David is not writing a letter.
 From the fact that for all x_14, if x_14 were an electrician, then x_14 is a police officer we can infer that if William were an electrician, then William is a police officer. From the fact that if it is sunny, then William is a police officer, that if William were an electrician, then William is a police officer, and that it is sunny or William is an electrician we can infer that William is a police officer. Finally, from the fact that if William were a police officer, then David is writing a letter, and that William is a police officer we can infer that David is writing a letter, which contradicts that David is not writing a letter. Therefore, the answer is no.