Consider the following premises. For all x_3, if x_3 plays squash, then x_3 is a taxi driver. For all x_3, if x_3 were a taxi driver, then x_3 is playing squash. For all x_3, if x_3 were a taxi driver, then x_3 is playing squash. Can we infer the following from them? For all x_3, if x_3 were a taxi driver, then x_3 is playing squash.
That is one of the premises. Therefore, the answer is yes.