4.Bd2 Qe7 5.Nc3: the knight line is variation 2 of 6 in the Bogo-Indian Defence course, a intermediate opening course for Black (ECO E11). It runs 24 moves and begins 1. d4 Nf6 2. c4 e6 3. Nf3 Bb4+ 4. Bd2 Qe7 …. White develops the knight to c3 and invites Black to take it. Black trades on c3 and then on c3 again with the knight. With ...d6, ...Nd7 and ...e5 Black builds a sound centre. In the lesson every move is explained on a board and then drilled; it is free.
Move by move
1. d4 – White takes the centre.
1... Nf6 – Black develops and watches e4.
2. c4 – White gains space.
2... e6 – Black opens the f8 bishop.
3. Nf3 – White develops and avoids the pin on c3.
3... Bb4+ – The Bogo-Indian. Black develops with check.
4. Bd2 – White blocks the check.
4... Qe7 – Black guards the bishop with the queen.
5. Nc3 – White develops and lets Black take on c3.
5... Bxc3 – Black takes. White must take back with the bishop.
6. Bxc3 – White takes back.
6... Ne4 – The knight hits the c3 bishop.
7. Qc2 – The most common move. The queen guards c3.
7... Nxc3 – Black trades the knight for White's good bishop.
8. Qxc3 – White takes back with the queen. Now the queen aims at g7.
8... d6 – The safe move. Black prepares e5 and opens the c8 bishop.
The lesson goes on for 8 more moves, each with its explanation.
chessGM