Beginner Exercise 15 / Solution

Seki  

threatens to make two eyes with a next.

Var 1 - Seki  

If Black plays , makes seki. Then, if Black plays inside, White gets a bent four or a straight four and lives. If White plays inside, he only gets three in a row, and dies. The circled point is the only possible weakness, but Black cannot get there before White connects.

Var 2 - White lives  

White has two eyes whatever happens. ( at a is a careless mistake - at kills.)

Doesn't work  

does not work, because reduces White to one eye.