What is the rule when adding es to a word?

There isn't one single rule for adding "es" to a word. It depends on the specific word and the context. Here's a breakdown:

Common Cases:

* Plural Nouns: We add "es" to nouns ending in "s", "x", "ch", "sh", and "z" to form their plural forms.

* Example: bus -> buses, box -> boxes, church -> churches, brush -> brushes, buzz -> buzzes

* Third-Person Singular Verbs: We add "es" to verbs ending in "s", "x", "ch", "sh", and "z" in the third-person singular present tense.

* Example: He washes the dishes. She catches the ball.

Exceptions:

* Nouns ending in "o" often add "es": hero -> heroes, potato -> potatoes, tomato -> tomatoes

* But there are exceptions: radio -> radios, piano -> pianos

* Nouns ending in "y" preceded by a consonant change the "y" to "i" and add "es": baby -> babies, city -> cities, story -> stories

* But if "y" is preceded by a vowel, only "s" is added: boy -> boys, toy -> toys

* Some words are irregular and don't follow standard rules: child -> children, woman -> women, mouse -> mice

Key Points:

* Always check a dictionary: If you're unsure whether to add "es" or "s" to a word, consult a dictionary.

* Consider the context: The part of speech (noun, verb, etc.) and the tense of the verb will affect whether you add "es" or "s".

Let me know if you want to explore any specific examples or have more questions!