Deal 4
 
  4♠
OL: J
♠ A 10 5
Q 6 3
8 7 4 2
♣ J 8 5
 
 WEST  NORTH  EAST  SOUTH
1♠
pass2♠pass4♠
passpasspass

You are West. The bidding has been as shown.

You lead the J, covered by dummy's Q and won by East's K.
East wins the A at the second trick and continues with a small ruffed by South.

South then plays the ♠4 from his hand.
Do you play low? or play the ♠J to force dummy's ♠A?

When you have made your choice click NEXT .
♠ K J 3
J 10 8 5
10 6
♣ 9 7 6 4

A K 2

  ♠ 4 2
9 4

 

 
Deal 4
 
  4♠
OL: J
♠ A 10 5
Q 6 3
8 7 4 2
♣ J 8 5
  Play the ♠3.

If South decides to finesse the ♠10 then you will still win the one ♠ trick which you are entitled to win.

However, with South holding the ♠Q it would be very logical for him to go up with the ♠A then lead back toward his ♠Q, playing East for the ♠K.
If he plays this way you will get two tricks and defeat the contract.

 Deal 5 
♠ K J 3
J 10 8 5
10 6
♣ 9 7 6 4
♠ 8 6
A K 7 2
9 5 3
♣ Q 10 3 2
  ♠ Q 9 7 4 2
9 4
A K Q J
♣ A K