Chopsticks at restaurants are eco-friendly.
All disposable chopsticks are made from trees. Some chopsticks are eco-friendly. Either disposable chopsticks or reusable chopsticks.  If chopsticks are made from metals, then they are not made from plastics.  All reusable chopsticks are made from metal. Chopsticks at restaurants are either made from metals and made from plastics, or neither made from metals nor made from plastics.
∀x (DisposableChopsticks(x) → MadeFromTrees(x)) ∃x (EcoFriendly(x)) ∀x (DisposableChopsticks(x) ⊕ Reusable(x))  ∀x (MadeFromMetals(x) → ¬MadeFromPlastics(x)) ∀x (Reusable(x) → MadeFromMetals(x)) ¬(MadeFromMetals(chopsticksAtRestaurants) ⊕ MadeFromPlastics(chopsticksAtRestaurants))