North-South vulnerable.  
South deals.
                              NORTH
                              S: Q 4              
                              H: K 6         
                              D: K 9 8 4     
                              C: K Q J 10 9
            WEST                             EAST
            S: J 8 5                         S: 6 3          
            H: 10 8 7                        H: A J 5 4 2  
            D: 10 5                          D: A J 7 3 2         
            C: A 6 5 4 3                     C: 2           
                              SOUTH                         
                              S: A K 10 9 7 2
                              H: Q 9 3      
                              D: Q 6       
                              C: 8 7
The Bidding:      
                  SOUTH    WEST    NORTH    EAST                  
                   2S      Pass     2NT(1)  Pass
                   3S(2)   Pass     4S  (All Pass)
1.  Asking for an ace or king outside the spade suit.  
2.  Denies an outside ace or king.
     Opening Lead: CA 
     This hand is very simple and yet it illustrates a complex
thought process that will improve your game.  West is on opening
lead.  If he decides to lead a red card the defense is easy and
should always come to three aces and a club ruff for a one trick
set.  But what if he decides to lead the ace of clubs?  Partner
contributes the deuce and West must decide how to continue.
     The thought process should be to stop and determine which
clubs you cannot see.  It is pretty obvious that the eight,
seven, and two are all that are available for East and South.  If
East held all three he would play the deuce and South would ruff. 
South did not ruff but followed with the seven.  Can East have
the eight?  If he did, what card would he play from the holding
of eight-two?  If they are playing standard carding, he should
play the eight from this combination.  So the two must be a
singleton and you must continue with another club because you are
never going to be on lead again in this hand.
     What if the club suit is distributed differently and East
plays the seven?  If South follows with the two then the seven
should be a singleton.  In this case, South should false card
with the eight and hide the two.  Also, if East's singleton is
the eight it will be difficult to determine what is correct.
     The important thing is to train yourself to think along
these lines to improve your defense and declarer play.
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