Consider the following premises. For all x_12, x_12 will make tea if and only if x_12 will play a game. Thomas is making tea or Thomas is not an office clerk. Can we infer the following from them? If Thomas were an office clerk, then Thomas is playing a game.
 From the fact that for all x_12, x_12 will make tea if and only if x_12 will play a game we can infer that Thomas is making tea if and only if Thomas is playing a game. From the fact that Thomas is making tea if and only if Thomas is playing a game we can infer that if Thomas makes tea, then Thomas is playing a game. From the fact that Thomas is making tea or Thomas is not an office clerk we can infer that if Thomas were an office clerk, then Thomas is making tea. Finally, from the fact that if Thomas were an office clerk, then Thomas is making tea, and that if Thomas makes tea, then Thomas is playing a game we can infer that if Thomas were an office clerk, then Thomas is playing a game. Therefore, the answer is yes.