restricting the white knight with a huge advantage.

Preventing an enemy attack with ...b5-b4 and ...a5-a4.

The most consistent choice.

By attacking f2 Black interferes with the plan of Rdg1 and g4-g5.

A less active defence permits 5 f3 with central activity.

Preparing Bc3 with a promising attack.

An excellent measure of restriction, which takes the e4-square away from several black pieces, and soon d5 as well.

1...Nf5 2.Qc3 Bb7 3.e4 , keeping the advantage.

Fixing a target on a7. We can also notice that the bishop on a8 has turned into a very passive piece.