∀x (¬Admit(x, mistake) → ¬GoodTeacher(x))
∃x ∃y (WellInformed(x) ∧ WellInformed(y) ∧ ¬Admit(x, mistake) ∧ ¬Admit(y, mistake) ∧ ¬(x=y))
∃x ∃y (GoodTeacher(x) ∧ GoodTeacher(y) ∧ ¬WellInformed(x) ∧ ¬WellInformed(y) ∧ ¬(x=y))