Middlegame

The middlegame in chess refers to the portion of the game that happens immediately after the opening (usually the first move after the procession of moves that make up a standard opening) and blends somewhat with the endgame, usually when queens are traded. During this time, players will attempt to strengthen their positions while weakening their opponent's, both by careful arrangement of the pieces for prepared attacks and defenses and by whittling away at their opponent's numbers. The middlegame usually involves a good deal of trading; studying how to trade successfully is important.
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