{"id":1845,"date":"2020-11-12T10:12:48","date_gmt":"2020-11-12T09:12:48","guid":{"rendered":"http:\/\/www.englishforums.com\/blog\/?p=1845"},"modified":"2026-08-08T10:42:51","modified_gmt":"2026-08-08T10:42:51","slug":"years-old-or-years-old","status":"publish","type":"post","link":"https:\/\/www.englishforward.com\/blog\/years-old-or-years-old\/","title":{"rendered":"Years old or Years-old: Whats the Difference?"},"content":{"rendered":"

Year Old vs. Years Old: Grammar and Hyphenation Rules Explained<\/h1>\n
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Quick Summary:<\/b><\/p>\n

Use “years old”<\/b> (plural, no hyphens) when the age comes after<\/i> a verb (e.g., “My son is five years old”<\/i>). Use “year-old”<\/b> (singular, with hyphens) when the age comes before<\/i> a noun as an adjective (e.g., “My five-year-old son”<\/i>) or functions as a standalone noun (e.g., “She is a three-year-old”<\/i>).<\/p>\n<\/blockquote>\n

Introduction: Why Stating Age Causes Confusion in English<\/h2>\n

Expressing a person’s or object’s age seems like one of the simplest things you can do in any language. However, in English, writing about age introduces tricky grammar choices.<\/p>\n

Consider these two sentences:<\/p>\n

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  1. \n

    Incorrect:<\/i> “My son is five year old.”<\/p>\n<\/li>\n

  2. \n

    Correct:<\/i> “My son is five years old.”<\/p>\n<\/li>\n<\/ol>\n

    Why is the first sentence completely wrong while the second is correct? And why would that same sentence change to “My five-year-old<\/b> son”<\/i> when we rearrange the words?<\/p>\n

    Because English uses age expressions as nouns, adjectives, and predicate descriptors, picking between “year old,”<\/b> “years old,”<\/b> and using hyphens<\/b> can quickly get confusing. This comprehensive guide breaks down the essential grammar rules so you can state ages accurately in speech, academic writing, and everyday conversation.<\/p>\n

    The Base Rule: Verbs Used When Stating Age<\/h2>\n

    Before looking at “year” versus “years,” we must address a common foundational error made by English learners.<\/p>\n

    In many languages (such as Spanish, French, Italian, and German), age is expressed using the verb to have<\/i>. For example, in Spanish, one says “Tengo diez a\u00f1os”<\/i> (literally: “I have ten years”<\/i>).<\/p>\n

    In English, however, we never use “have” or “has”<\/b> to state a person’s age. Instead, we always use the “be” verbs<\/b> (am, is, are, was, were<\/i>).<\/p>\n

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    Verb Choice Structure for Age:\r\n\r\n  [ Incorrect ] ---> \"I have ten years old.\" \/ \"She has five years.\"\r\n  [ Correct   ] ---> \"I am ten years old.\"  \/ \"She is five years old.\"\r\n<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n
    Once you master using the verb to be<\/i>, you can apply the four core rules for choosing between “year old” and “years old.”<\/p>\n
    Year Old vs. Years Old: 4 Essential Grammar Rules<\/h2>\n
    Rule 1: Singular (1 Year) vs. Plural (2+ Years)<\/h3>\n
    When stating age directly after a verb, the choice between “year” and “years” depends entirely on whether the number is one or greater than one:<\/p>\n