Hands are from Adventures in Bridge, October 3, 2018.
West (Partner): ♠63 ♥K6 ♦A92 ♣KJ8642
East (You): ♠K109872 ♥A94 ♦Q54 ♣7
The auction goes: 1♣ by West (Partner); pass by North (who holds ♣AQ10x), 1♠ by East (you); pass by South. Partner chose to rebid 2♣. (I would rebid 1NT.) Expecting a singleton spade on the auction, you rebid 2♠ because it is usually better, on misfits, to play in the trump suit of the weaker hand. (The stronger hand will have useful high cards for the weaker. The weaker hand will not be of much use to the stronger with just a long suit.) LHO doubled belatedly, presumably for the red suits, and RHO passed, electing to defend.
You escape a trump lead as South leads the ♥Q. Play the ♥K, the ♥A, and ruff the third round of hearts on Dummy. Now, a low spade from Dummy to your ♠10, false-carding since the ♠10987 and ♠6 from Dummy are all equals). The ♠10 wins, with the ♠5 falling from the LHO.
Hoping that South has the ♣A for her double, you lead a club to the ♣K, but it loses to the ♣A on your right. RHO thinks a bit and plays the ♠A and then the ♠Q. It looks like RHO has the ♣Q as well as the ♣A and does not want to break the diamond suit. You win the ♠K, and play another round of spades to North's ♣J. (LHO has been discarding encouraging diamonds and hearts on the spades.)
RHO is finally forced to lead a diamond and plays the ♦6. You play low from your ♦Q54 and LHO inserts the ♦J to force the ♦A on Dummy. Now you play the ♦2 from Dummy and RHO is forced to play the ♦10, having starting with ♦106. You cover with the ♦Q which loses to LHO’s ♦K, but you have now promoted Dummy's the ♦9 to a winner. You actually make an overtrick.
East: ♠752 ♥J2 ♦A963 ♣K1053
West: ♠8 ♥AKQ964 ♦J84 ♣A87
West is declaring in 4♥ after RHO bid 2♠ over partner’s forcing NT, and rebid 3♠ after a 3♥ call by West.
The lead is the ♠9 to ♠10. LHO continues with the ♠A and you ruff.
You have interesting spots in both minor suits, so you want to take all your chances. Play one high heart from your hand and then a heart to the ♥J. Both opponents follow. Now, lead a low diamond toward your ♦J84. If RHO has the ♦Kx, she unlikely to duck it. RHO plays the ♦10, and you cover with the ♦J, as LHO takes the ♦K. Look at how those lovely diamond spots are shaping up. LHO is out of spades and hearts, so she returns the ♣4. You play low from Dummy and RHO plays the ♣J.
Now, you pull the last trump, and RHO follows. So, RHO started with seven spades and three hearts. She has followed to one diamond and one club. The Rule of Restricted Choice makes the odds 2:1 that North has the ♣Q, so you play a club to the ♣10 and it wins, as South discards a spade. [Incidentally, North led the ♣4 originally and played the ♣2 on the second round, confirming that she started with five clubs originally.] South bid twice and did not preempt despite having seven spades. The only other high card she could have in her hand is the ♦Q, which must be doubleton based on your count of the hand.
Therefore, you cash the ♦A. RHO’s ♦Q falls, and Dummy's the ♦9 is once again a winning trick!