Deal 14
 
 
 
♠ Q J 2
K 10
K Q 8 6 5
♣ Q 8 7
 
 WEST  NORTH  EAST  SOUTH
1
pass2pass2
pass4passpass
pass

South opens 1 and North responds 2.

South has a good-looking hand, but needs to find a trump suit before she starts showing her extra strength, so she bids just 2.

Knowing that South holds 6 s, North can support with the honor doubleton so he agrees the trump suit with a Fast Arrival bid of 4.

South has some extra strength, but not enough to push on after North's weak bid.
Notice that if South DID try a 4♠ Control bid North would just bid 5 and the pair might be one trick too high.

 Deal 15 
  ♠ A
A Q J 7 5 3
7 4 2
♣ K J 4