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(Position after Black's Rh6) Its my game against Kahane Bhavesh..I was having white pieces and was exited with the fact that Black's king was still in the center,so my basic enctint was to attack some how on the king.I made some premature moves in order to attack his king before..After thinking I released that Black has a threat of Rg6 hitting my g2 pawn..And it would be helped by the monster of b7                      I played the terrible move Na5??? putting the knight on rim without thinking as I wanted to swap the bishop first. Now its Black to play Black has a long think of 20 minutes and played the move which I didn't calculated..Can you guess what I missed in the game..and calculate all the variations?? My opponent played that move but didn't continue correctly..Can you do better than my opponent ?? 

This is from my online game Black has just played Qxg5...Please analyse all the variation and submit your calcuations or check the full game below

This position was reached in Rubinstein -- Burn, Ostende 1906

One of the biggest mistakes chess players makes while solving positions is just guessing moves...They just guess moves and hope one of the answers they give will work.This is really a bad habit.If you want to improve your game you must start to work on your calculations..Think as if it the position in your game and try to calculate.Please give complete answers with variation...

So the position is from one of my online game,played on www.chess.com. I am having white piece...At this point I am a complete queen down but I posses a strong threat of discover check with a mate..Its Black's move.So what do you think is black best move..Can black mange to save the game or it lost anyways..Please post your answers with variations and signs

Black to move. How should black proceed? Source: ChessToday.net

I am giving these few examples without quoting source and answers.Let's see if you could solve this positions...These positions are not so tough and are at the level below 1800 rating.Please quote answers in comment.