Are the quantifiers interchangeable?

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In other words, is it true that $\forall x \; \exists y\;\phi(x, y) \iff \exists y\;\forall x \; \phi(x, y) $?

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Every child has a father, but there is not a father for all children.

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$\forall x \in \mathbb{R} \exists y\in\mathbb{R}\,[x>y]$ is true, but $\exists y\in\mathbb{R}\forall x\in\mathbb{R}\,[x>y]$ is false.