∀x ∀y (Person(x) ∧ Product(y) ∧ ¬HaveEnoughMoneyFor(x, y) → ¬Buy(x, y))
∀x (Monitor(x) → Product(x))
∀x ∀y ∀z (Monitor(x) ∧ Monitor(y) ∧ Monitor(z) ∧ FourK(x) ∧ OneOEightO(y) ∧ TwoK(z) → MoreExpensive(x, y) ∧ MoreExpensive(x, z))
Person(john)
∀x (Monitor(x) ∧ TwoK(x) → ¬HaveEnoughMoneyFor(john, x))
∀x (Monitor(x) ∧ OneOEightO(x) → ¬Buy(john, x))