Plural Nouns:
* General Rule: Most nouns form their plural by adding an "s" to the end. For example: cat - cats, book - books, table - tables.
* Exception: For nouns ending in "s", "x", "ch", "sh", or "z", we add "es" to form the plural. This is because adding just an "s" would create an awkward pronunciation. Examples: bus - buses, box - boxes, church - churches, dish - dishes, quiz - quizzes.
* Other Irregular Plurals: Some nouns have irregular plural forms that don't follow any specific rule. These are exceptions to the general rules and need to be memorized, like child - children, man - men, woman - women, etc.
Third-Person Singular Verbs:
* Present Tense: To indicate an action done by a single person or thing (third-person singular), we add "s" or "es" to the base form of the verb in the present tense.
* General Rule: Most verbs add "s" to the base form: He walks, she eats, it runs.
* Exception: Verbs ending in "s", "x", "ch", "sh", or "z" add "es" for the third-person singular form: He kisses, she fixes, it watches, she washes, it buzzes.
Important Note: This "es" ending doesn't apply to all verbs. Some verbs have unique forms for the third-person singular (like "has" instead of "have" for "to have").
In summary, adding "es" is a specific way to create plural nouns and third-person singular present-tense verbs in English, following rules based on pronunciation and grammar.