Section 2. Chaksu (Article 9, 10)

Article 9. The Resiricted Chaksu, pae ( ko in Japanese)
  In a position where one stone has just been captured, the player with the turn may not take back to leave the same position. This is called pae (ko in Japanese). But this prohibition lasts one turn only.
(Figure 5-1, 5-2)

 



Figure 5-1

White can play
at 1 to capture the marked
Black stone,
and Black can
play at A to capture a

White stone



 


Figure 5-2

Black can not
play at A
unless Black
has played
a Paegam
(ko threat).



Article 10. Capture
  If the placement of a stone removes a group's last liberty, this group must be immediately taken from the board (Figure 6-1).
At the end of the game groups that have not secured life are removed, whatever the number of liberties.


Figure 6-1
White can play
at the positions
marked 1.



 

Figure 6-2
Black's two
stones are removed at
the end of the game without
any further
move from White.