In standard contemporary Modern English, you is both singular and plural; it always takes a verb form that originally marked the word as plural,. This was not always so. Early Modern English distinguished between the plural ye and the singular thou. As in many other European languages, English at the time had a T–V distinction, which made the plural forms more respectful and deferential; they were used to address strangers and social superiors. This distinction ultimately led to familiar thou becoming obsolete in modern English, although it persists in some English dialects. Because thou is now seen primarily in literary sources such as the King James Bible or Shakespeare, it is now widely perceived as more formal, rather than familiar. Although the other forms for the plural second-person pronoun are now used for the singular second-person pronoun in modern English, the plural reflexive form "yourselves" is not used for the singular; instead "yourself" is used for the singular second-person reflexive pronoun.
Informal plural forms
Although there is some dialectal retention of the original plural ye and the original singular thou, most English-speaking groups have lost the original forms. Because of the loss of the original singular-plural distinction, many English dialects belonging to this group have innovated new plural forms of the second person pronoun. Examples of such pronouns sometimes seen and heard include:
you guys – United States, particularly in the Midwest, Northeast, South Florida and West Coast; Canada, Australia. Gendered usage varies; for mixed groups, "you guys" is nearly always used, though for groups consisting of only women, forms like "you girls" or "you gals" might appear instead, though sometimes "you guys" is used for a group of only women as well.
You is usually a second person pronoun. It is also used to refer to an indeterminate person, as a more common alternative to the very formal indefinite pronounone.
Etymology
You is derived from Old English ge or ȝe, which was the old nominative case form of the pronoun, and eow, which was the old accusative case form of the pronoun. In Middle English the nominative case became ye, and the oblique case was you. In early Modern English either the nominative or the accusative form had been generalized in most dialects. Most generalized you; some dialects in the north of England and Scotland generalized ye, or use ye as a clipped or clitic form of the pronoun. The specific form of this pronoun can be derived from Proto-Indo-European *yūs. It is most widespread in the Germanic languages, but has cognates in other branches of Indo-European languages such as Ved. yūyám, Av. yūš, Gk. humeis, Toch. yas/yes, Arm. dzez/cez, OPr. ioūs, Lith. jūs, Ltv. jūs, Alb. juve/ju. In other Indo-European languages the form derived from Proto-Indo-European *wō̆s began to prevail: Lat. vōs, Pol. wy, Russ. вы. In the early days of the printing press, the letter y was used in place of the thorn, so many modern instances of "ye" are in fact examples of "the" and not of "you". This use of letters in printing may have indirectly helped contribute to the displacement of thou by you, and the use of you in the nominative case.
