Chess Opening Theory/1. d4/1...d5/2. c4/2...e6

=Queen's Gambit Declined=

2...e6
With 2...e6, Black declines the Queen's Gambit in the traditional fashion. 2...e6 bolsters the d5 pawn and opens a diagonal for the development of Black's dark-squared bishop. However, 2...e6 also blocks the c8-h3 diagonal for Black's light-squared bishop. Finding a way to productively develop this piece is a perennial challenge for Black players in the QGD.

Theory table
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'''1. d4 d5 2. c4 e6'''