Small card led.
In trumps, play a small one.
In plain suits, with five in suit, play a small one if strong in trumps; the queen if weak in trumps.
Knave led.
Play ace. It is useless to cover with the queen, as the leader cannot hold the king (see Analysis of Leads).
These instructions assume ordinary original leads from strength. If ace or queen is turned up, some players lead knave, from king, knave, ten. If you know this is the practice of your right hand adversary, you should exercise your judgment as to covering with ace or queen.
Also towards the close of a hand, knave might be led from king, knave for various reasons, perhaps as the best chance of saving or winning the game or a point, or as a false card. No rule can be laid down for such cases.
Ten or nine led.
Play queen.