import logic

example {a b c : Prop} : a → b → c → a ∧ b :=
begin
  intros (Ha, Hb, Hc),
  clears (Hc, c),
  apply  (and.intro Ha Hb),
end

example {a b c : Prop} : a → b → c → c ∧ b :=
begin
  intros (Ha, Hb, Hc),
  clears (Ha, a),
  apply  (and.intro Hc Hb),
end