Incorporating a personal pronoun with a number expresses a plural pronoun in American Sign Language (ASL). This process is known as numeral incorporation in ASL linguistics.
A personal pronoun in ASL can incorporates with a number between one and five.
This indexing is incorporated with the manual number two. It means you and I (or me).
It is two-you, which means two of you or both of you in English.
The signer incorporate they with a number of two, which indicates both of them or two of them.
It means three of you. Notice that the movements of the handshapes number one (index finger) and 2-handshape are different from the numbers from three to five, in which the index finger points. The 2-handshape moves back and forward. The 3- to 5-handshapes move in circle.
It means we-three or three-of-us. The signer uses a different location that is closer to her physical space to indicate "us" or "we" in contrast to "you" where the location is farther from her physical space.
you-three, you-five, we-five, we-four, etc. (see some more in the dictionary).
These ASL pronouns can incorporate a number up to five. If it is more than 5 people, instead use 1-handshape (index finger) in a circular or arc motion after a number (or vice versa). E.g. "seven we", "nine them/they/those", etc. Or, one also says "we eight people..."