$∀x(N(x)→∃y∃x(N(y) ∧ x ≥ y))$ - bounded variables

Question

Using this formula I am trying to see which variables are bounded by which quantifiers. $∀x$ universal quantifier bounds all the $x$'s in the formula as they are all within its bracket. However, does that mean I ignore the $∃x$ which is within that bracket, or should I use substitution and make $∀x(N(x)→∃y∃z(N(y) ∧ z ≥ y))$ instead.

Thanks in advance.

Answer 1

Using substitution is correct and it helps avoid confusion.