Consider the following premises. There is at least one x_1 for which x_1 will climb a mountain. For all x_1, x_1 will not climb a mountain. Can we infer the following from them? For all x_1, x_1 will not play squash.
 From the fact that there is at least one x_1 for which x_1 will climb a mountain we can infer that there is at least one x_1 for which x_1 will climb a mountain or x_1 will play squash. Finally, from the fact that there is at least one x_1 for which x_1 will climb a mountain or x_1 will play squash, and that for all x_1, x_1 will not climb a mountain we can infer that there is at least one x_1 for which x_1 will play squash, which contradicts that For all x_1, x_1 will not play squash. Therefore, the answer is no.