ЕСЛИ БЫ МОЛОДОСТЬ ЗНАЛА, ЕСЛИ БЫ СТАРОСТЬ МОГЛА

Young people are inexperienced; old people have experience, but they are too weak to make use of it Var: Cf: If the young knew, if the old could, there's nothing but would be done (Br.). If the young man would and the old man could, there would be nothing undone (Am.). If youth but knew and age but could do (Am.). If youth but knew, if age but could (Br.)