第三人称复数主格代词，“所涉及或最后提到的人或物”，约公元1200年，来自斯堪的纳维亚语（古诺尔斯语 þeir，古丹麦语 þer， þair），最初为阳性复数指示代词。到公元1400年左右，它已取代中古英语 he， hei，来自古英语 hi， hie，为 he， heo “她”， hit “它”的复数形式。
The most important importation of this kind [from Scandinavian to English] was that of the pronomial forms they, them and their, which entered readily into the system of English pronouns beginning with the same sound ( the, that, this) and were felt to be more distinct than the old native forms which they supplanted. Indeed these were liable to constant confusion with some forms of the singular number ( he, him, her) after the vowels has become obscured, so that he and hie, him and heom, her ( hire) and heora could no longer be kept easily apart. [Jespersen, "Growth and Structure of the English Language"]
这种类型[从斯堪的纳维亚语到英语的]最重要的引入是代名词形式 they， them和 their，它们很快进入了英语代词系统，开始于相同的音（ the， that， this），并被认为比它们取代的旧本土形式更为独特。事实上，这些形式在元音变得模糊后，常常与某些单数形式（ he， him， her）混淆，因此 he和 hie， him和 heom， her（ hire）和 heora难以轻易区分。[Jespersen, "Growth and Structure of the English Language"]
they的斯堪的纳维亚语来源是原始日耳曼语 *thai，主格复数代词，来自原始印欧语 *to-，指示代词（参见 that）。
约公元1400年起意为“人们一般”。1886年起证实口语中使用they指“匿名的权威人士”。They say意为“据说”出现在米尔顿的作品中。
1520年代起用于单数名词，特别是与 every， any等词搭配。
[Y]ou desire to be just and honest and to give every Body their due .... [William Notcott, "Jesus Christ Most Precious to Every True Believer," 1735]
