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I lost this game some days ago because I didnt defend properly. Ideas? Begin at the 33th move. Very locked position.

I actually think you played that very well except for taking the rook on move 39. I think that you were winning up until that. Here is what I think should have been played. I tried to include several variations. If you can think of anything else, go ahead and ask. Let me know if you need me to explain it better, too.

And another question. What do you think about my knight improvement in this game. 5..., Ng6 and 7...Nb6? Are those placed okay for knight in caro kann? I was played this game very experimentally.

Actually you have a little more room for error in a closed position, because you need to be thinking more long-term than immediate tactics. Of course if you make a lot of mistakes, you will lose whether the position is open or closed, but in a closed position you often have a chance to correct your mistakes before your opponent can punish it.
I think the Ng6 idea was perfectly fine. In fact, I think that is probably where the knight should have gone anyway. The Nb6 idea, however, I am not so sure about. It is relatively passive on b6. If white did not take it and played 10. Qc1 when you played 9. ...Nc4, the knight would have simply been misplaced. Generally, the reason you keep the knight on d7 in the Caro-Kann is to support a ...c5 break at some point. You can get a lot more counterplay after you make your ...c5 break, because then your pieces can actually get out and do things.
It can be a little tricky to mix defense with counterattack, but if you only defend, you will have a hard time winning games if your opponent does not make a large mistake.

I can't quite agree with the knight positioning. It looks quite well in that game, but you can easily get into trouble while you move them into position, if your opponent is more aggressive. Try to move out your bishops as fast as possible, this way you can leave those knights on d7-e7. I just started to look into Caro-Kann myself, and had some really good games. Will try to post one if I find it

Somehow i never liked this line because of 5. Qxd3 seems to helps the opponent bring out its queen with tempo, to a centralized position. Even though I like your king knight improvement with a queenside castle. seems very stable. Is anybody here who doesnt take the bishop with bishop in the 4th move? is there any other line, or its definitely the best?
Thx for this post, I learned a bit from your positional play!!!

I think 4. ...Bxd3 is considered best. It might even be considered the only move in that line. The reasoning behind it is that white needs that light squared bishop for a lot of attacking ideas, so by trading it off, it makes the game a lot calmer.

The moves that jump out at me are Nh4, Bd3, and Bg2. I analyzed for a bit, and I think Nh4 is the correct move.
Simply from a practical point of view, Nh4 forces off the black light squared bishop, which has to be good since the center is open. (Nh4 Bg6 [Be4 f3!] Nxg6 hxg6 Bg2)
Bd3 is probably my second choice, since it makes the bishop active and threatens to trade off the light squared bishop. The black light squared bishop is better than the white one here, which is why I think the trade is reasonable.
Bg2 seems like a safer, "I'm not sure what I should be doing, but this move can't possibly be bad" kind of move.

Bg2 is considered bad by Waitzkin itself.And this is the main question. Why?
Nh4 is interesting, but after Be4 black makes a strong outpost, what makes more trouble and driving out the bishop makes our kingside pawn structure weaker, right?
Yes, Bd3 is reasonable, i guess i would make that move in a real party. Even though...it's not the best.

The reason why Bg2 isn't so good is that it is kind of passive. The a8-h1 diagonal isn't very strong due to the c6 pawn being firmly placed. Its not really that "bad" per se, it just isn't a very strong move. Its the kind of thing that Master+ players can easily exploit, but anyone below that would struggle to punish it.
My idea after Nh4 is ...Be4 f3 Bg6 Nxg6 hxg6 f4. Really I don't think that it is too weakening, since it is difficult for black to break into the white position.
What is considered the best move there?
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