Deal 19
 
 
 
♠ K 9 2
A K 8 7 4
K 10 7
♣ 10 8
 
 WEST  NORTH  EAST  SOUTH
1Double2♣
passpasspass

North opens 1 and East Doubles.

After the intervening Takeout Double 2/1 is OFF.
If South had 10 or more points she would Redouble.
So even with only 9 points South can bid 2♣ without fear that North will think she has a strong hand.

North also knows everything mentioned above so he passes.

 Deal 20 
  ♠ J 10 6
9
8 5 3
♣ K Q J 9 5 2