Please review my games against Cosumi

I am a fairly strong chess player who picked up Go a week ago. Started by playing 9x9 games against Igowin and going through Go ebooks (like Black to Play: Train the Basics). By now, I can tell when stones are in atari (thus not giving away free stones), but not much more. I decided to try playing some 19x19 games against a computer (at

For the first game, please refer to

Specific points:

  • I could have captured a stone at move 30 but only did at move 34. Why did Cosumi not connect to save its stone? Should I have captured immediately, settled the group (as in the game) or done something else?
  • How do I tell when playing a cut like move 38 is a good idea?
  • Moves 54, 56 and 58 were to prevent the 6-stone Black group from linking with the Black stones at the bottom, thus ensuring the group is dead and securing some territory for myself. Was I being too cautious? How could I tell when the Black group was certainly dead? How else could I have killed it and secured the territory?
  • Was move 62 at the right place? Should I have played move 70 earlier? Whole-board vision seems too advanced at my current level and I only attack where I am strong. Nevertheless, I knew I had to limit his potential territory and secure more for myself.
  • Moves 81-84 and 123-126 seem to be a standard sequence. Did I play this sequence correctly?
  • I think I reacted badly to moves 97 and 99. What would be a better response?
  • Of course, move 130 is a mistake and the Black group in the top-left corner had already secured life.
  • Why did Cosumi play in its own territory on move 133 and 135, thus losing points? Pretty sure I cannot atari below 135.

Thanks for the advice!

Welcome to OGS, @springyboard!

Here is a review for you:
I hope it helps.

The review was very helpful. Thank you so much!

Will apply your advice in my next few games against Cosumi, then post another game (hopefully with a smaller losing margin) here for review.

If I play the move 6 that you suggested, could Black take the corner (such as by playing at C17)?