Hi! In short, in d4 - d5 positions, c4 is white's main pawn break as early as on the 2nd move (Queen's Gambit) Often times, black can take the pawn but can never hang on to it. Whether black hangs on to the pawn or not, white often gets some form of comepnsation.
In the following position, if black takes on c4, they move their d5 pawn away from the centre. For the pawn, white has the following forms of compensation:
- White has more control over the centre. With the threat of e4 - e5 or Bxf6 followed by e4 - e5, black has to resort to passive defensive measures.
- White's g2 bishop is now extremely strong, having the whole g2 - b7 diagonal to itself. A move like Nh4 could activate the bishop while threatening to take on b7 and trade off black's contesting light-squared bishop on f5 at the same time.
These two factors alone are enough for the pawn but to make things worse for black, black can't even hang on to the extra material. A move like b5 is always too unstable and weakening. Worst case scenario, white can always play a4 (to prevent b5) and then win back the pawn with a move such as Nd2, Ne5, or even Qe2.
[Event "?"]
[Site "?"]
[Date "2024.01.28"]
[Round "?"]
[White "Player 1"]
[Black "Player 2"]
[Result "*"]
1. Nf3 d5 2. g3 Bf5 3. Bg2 Nf6 4. d4 e6 5. O-O Bd6 6. Bg5 O-O 7. c4 *