Gokyo Shumyo, Section 1, Problem 2 / Solution

Main line  

is the only move. After , the points a and b are miai for life.

Related proverb: strange things happen at the one-two point - in this case you need to know which of the two 1-2 points, of course.

2 and 3 are miai (i)  

Black has two sure eyes at a and b.

2 and 3 miai (ii)  

If White next blocks at a, Black makes another eye with b. And if White draws out at b, Black enlarges the eye with a.

NB: if White has a stone on one of the circled points, or at a, her move at b suddenly works and Black is dead.

Without supporting stones  

White's attempt to escape fails.

Wrong (i)  

is wrong. After , and seem to make the most of it, but when White cuts at it's all over.

Wrong (ii)  

If Black plays at the other 1-2 point, it is also wrong. and are miai for the kill. After , Black can play neither a nor b because of shortage of liberties.

Wrong (iii)  

here is also wrong. White can even respond at ease to the hanes at and , because whatever Black does, the points a and b remain miai for the kill.

Wrong (iv)  

Finally, what about making the corner eyespace as big as possible, with here? White simply blocks at and there is no way to make life.