Concept notes: In English grammar, when expressing age, the correct form is to use a hyphen and the singular form of "year." For example, "fifteen-year-old" is correct, not "fifteen-years-old." This rule applies to all ages and is crucial for correct written communication.
Explanation: In the sentence "She adopted a fifteen-years-old Sikkimese boy to travel with her," the grammatical error lies in the expression of the boy's age. The correct form should be "fifteen-year-old" instead of "fifteen-years-old."
To understand why this is the case, we need to delve into the rules of hyphen usage in English grammar. When expressing age, the correct form involves using a hyphen and the singular form of "year." For example, "five-year-old," "ten-year-old," and "fifteen-year-old" are all correct. The hyphen connects the number and the singular form of "year" to create a compound adjective that modifies the noun (in this case, "boy").
The misconception that leads to the error is the belief that "years" should be plural when used with a number and a hyphen. However, the rule is that "year" remains singular regardless of the number. This rule applies to all ages, not just "fifteen."
The other parts of the sentence are grammatically correct. "Adopted" is the past tense of the verb "adopt," which is used correctly to describe the action of taking in a child. "To travel" is a purpose clause that correctly indicates the intention of the action. "With" is a preposition that correctly indicates the relationship between the person and the child.
Understanding and applying this rule is crucial for correct written communication, especially in formal contexts such as competitive examinations and professional writing. It is important to remember that the singular form of "year" is used when expressing age with a hyphen, regardless of the number. This rule helps maintain clarity and correctness in written English.