Consider the following premises. For all x_4, if x_4 plays squash, then x_4 is cooking. There is at least one x_4 for which x_4 will cook if and only if x_4 will drink water. Can we infer the following from them? If we can, name the inference rule being used: For all x_4, the fact that x_4 plays squash does not imply that x_4 is drinking water.
That contradicts the premises. Therefore the answer is no.