In the Alekhine's Defence...
Black allows White to make several attacks on the knight
He replies by moving his Knight here
White moves Queen’s pawn forward
Black responds by moving this pawn
White wants to chase Black knight all over the board
Black Knight retreats here
And attacks this pawn
White moves this pawn
Controlling the center
Black can now attack White’s overextended pawns
White captures on g5
Black exchanges this pawn
Black exchanges this pawn
And takes White Queen
White takes Black Queen
White now has three weak pawns
And his King can no longer castle