The plural form of a noun is usually created by adding the suffix -(e)s. The pronouns have irregular plurals, as in "I" versus "we", because they are ancient and frequently used words going back to when English had a well developed system of declension. English verbs distinguish singular from plural number in the third person present tense ("He goes" versus "They go"). English treats zero with the plural number.
This is a companion discussion topic for the original entry at http://grammarerror.com/tags/grammatical-number