Signals & discards. Leading to a ruff
Try to give suit preference
Let's say the contract is 4 Spades, and your partner, on opening lead, played the 6 of Hearts. It happened that you had the A 8 7 4 in Hearts, so being third player you dutifully played high as you can, won the trick, and equally dutifully (and hoping for a ruff, judging by the length in both your holding and in dummy's) led the same suit back to partner, playing a 4 of Hearts.
Partner's 6 had indeed been a singleton (a very sensible opening lead), so partner ruffed your 4 of Hearts. Now he hopes you can win another trick immediately, and then lead back another Heart to let him ruff again and deeply annoy the enemy. Did you give him any guidance with that 4 of Hearts?
Well, yes, you did.
By choosing a 'low' little Heart ('low' = 2, 3 or 4) you told him that you'd like a lead back in the lower ranking of the two remaining suits, namely Clubs.
(2 remaining suits? - exclude both trumps and the suit that he ruffed - so exclude Hearts & Spades). And since you have an Ace in Clubs, you can win the trick and immediately lead another Heart to be ruffed again.
So with only 2 Aces, your team has won the first 4 tricks. And there's nothing the brilliant declarer can do, even with 32 HCP on his team.
Now try the quiz
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