Following @0xbitcoiner's suggestion to have puzzles with a more real context (#743441), here a try at something in that direction:
On a remote island, there are two types of people: truth-tellers, who always tell the truth, and liars, who always lie. You meet three people on this island: Alice, Bob, and Carol.
Alice says, "Bob and I are of the same type."
Bob says, "Alice and Carol are of opposite types."
Carol says, "Alice and I are of the same type."
Determine who the truth-tellers and liars are.