Dia. 2. Black blocks at 1, of course. There is no need for him to wonder what White may do afterward. Given a chance like this, only a feeble-minded player would be uncertain where to play - 'not this point, not here either, perhaps I should leave the position as it is.' Black's hand should be tremb...
Combinations are the heart of chess, as they say, and similarly tesuji (literally, "skillful moves") are the heart of Go. This book gives you a nice introduction. Here's an example of a tesuji, the "crane's nest", which is about as basic as it gets; it's sort of the Go equivalent of the smothered ma...