Attacking with Two Weapons (PHB)

__NOTOC__
A tricky fighting style available only to warriors and rogues is that of fighting with two weapons simultaneously. The character chooses not to use a shield in favor of another weapon, granting him a greater number of attacks, with a penalty to his attack rolls (rangers are exempt from the attack roll penalty).
When using a second weapon in his off-hand, a character is limited in his weapon choice. His principal weapon can be whatever he chooses, provided it can be wielded with one hand. The second weapon must be smaller in size and weight than the character's main weapon (though a dagger can always be used as a second weapon, even if the primary weapon is also a dagger). A fighter can use a long sword and a short sword, or a long sword and a dagger, but he cannot use two long swords. Nor can the character use a shield, unless it is kept strapped onto his back.
When attacking, all characters but rangers suffer penalties to their attack rolls. Attacks made with the main weapon suffer a -2 penalty, and attacks made with the second weapon suffer a -4 penalty. The character's Reaction Adjustment (based on his Dexterity, see Table 2) modifies this penalty. A low Dexterity score will worsen the character's chance to hit with each attack. A high Dexterity can negate this particular penalty, although it cannot result in a positive modifier on the attack rolls for either weapon (i.e., the Reaction Adjustment can, at best, raise the attack roll penalties to 0).
The use of two weapons enables the character to make one additional attack each combat round, with the second weapon. The character gains only one additional attack each round, regardless of the number of attacks he may normally be allowed. Thus, a warrior able to attack 3/2 (once in the first round and twice in the second) can attack 5/2 (twice in the first round and three times in the second).