Jack is a pupil.
No animals are plants.  All humans are animals. All pupils are human. All flowers are plants. If Jack is a human or a flower, then Jack is a human and a flower.
∀x (Animal(x) → ¬Plant(x)) ∀x (Human(x) → Animal(x)) ∀x (Pupil(x) → Human(x)) ∀x (Flower(x) → Plant(x)) Human(jack) ∨ Flower(jack) → Human(jack) ∧ Flower(jack)