Lead knave, in all suits.
Holding more than two small, follow knave with queen; holding two small, follow knave with king.
King, queen, knave, one small.
Lead king, then knave, in all suits.
If king forces ace, or if partner holds ace, the leader, on the appearance of the knave, is marked with queen and one small. If ace is not forced, the presumption is that the leader remains with ace, queen, exactly (see lead from ace, king, queen, knave).
King, queen, ten, and more than one small, in trumps.
Lead queen.
If queen wins the trick, follow with fourth best remaining in hand. King is marked; so, exclude the king, and on second lead continue with the fourth best of the small cards.
Sooner or later, the leader will be marked with at least five trumps originally, including king, ten; or, if he has not the ten, with at least seven trumps originally.
If queen forces ace, on the appearance of the king, the leader is marked with at least five trumps originally (one being the ten); or, if he has not the ten, with at least seven trumps originally.