As East, you hold:
Tired of these lousy hands? Take a slam-bidding seminar. :)
Seriously, a great way to improve is to focus more when you get bad hands like this--especially when they are in a quiz.
Against the auction shown below (2N-3N), partner leads the K. What do you play?
Partner continues as shown below. What can you conclude?
Declarer has the A, but there is no way to know the rest of the heart suit.
Declarer started with Ax (doubleton).
Declarer continues with the AKQJ. Partner discards a low spade on the third round and another spade as shown below. What do you discard?
Q or J