Final answer:
Two nouns that exist in both singular and plural forms are 'child' and 'leaf.' It's important to follow subject-verb agreement rules when constructing sentences with these nouns.
Step-by-step explanation:
Two nouns that exist in both singular and plural forms are child (children) and leaf (leaves). These nouns change form when shifting from singular to plural, demonstrating the irregular nature of English pluralization. Subject-verb agreement is crucial in constructing sentences with these nouns. For example, in singular form, you would say, 'The child is playing,' but in plural form, 'The children are playing.'
Subject-verb agreement is vital to maintaining proper grammar in English. When two or more singular nouns are connected by 'or' or 'nor,' the verb should be singular, as in 'Either a socket wrench or power drill is necessary.' However, if one of the nouns is plural and is closer to the verb, the verb should be plural: 'Either your uncles or your mother remembers the recipe.'