Beginner Exercise 110 / Solution

Summary  

No. Black can't cross the 3x3 gap.

There are many candidate moves so let us concentrate on more difficult ones - a keima, b kosumi and c attach.

Symmetry point  

is defeated by two clamping attachments, and . This line works for Black if the marked stone is missing (or results in a throw-in ko at if the marked stone is at a).

Kosumi  

tries a kind of "monkey jump on the second line", then White plays the attachment at . Next, descending at is key to prevent connection.

Attach  

! prevents connection by keeping options on the third line open. After , White pushes through the other side with .

Variation  

counter-clamp is an interesting try to make ko, but and separates the lower group even if Black wins the ko.