Be3 is the Classical Variation, where White aims for a slow buildup to a kingside offensive.

This can transpose to the Classical Variation of the French Defence after 4.

The knight move is a very common one in the Classical Variation and Qd2 is well met with 9...d5.

The Classical Variation arises after 3.

Be2, the Classical Variation, and 6.

After 6 Be2, the Classical Variation against the King's Indian Defense arises.

Bg5 is nowadays the main line of the Classical Variation (although 6...b5!?

Like the Classical Variation, it avoids the doubling of White's pawns.

Nc3, though in the 1980s, the Classical Variation with 3...Nf6 began a revival, and has since become more popular.

After 4 Be7, the Classical Variation of the French Defense arises.