To have a good understanding of Esperanto grammar, it's necessary to know some terms. Below, there is a list of these terms, with short explanations. (The explanations in this page aren't complete; they are only meant to give a basic introduction to the terms.)

Noun (Substantivo)

A noun is a name of a person, place, or thing. A noun answers the question "What is (it/he/she)?" For example: "person", "idea", "name" and "house". »

Plural (Pluralo)

Plural means that there are more than one thing. For example: "people", "ideas". In Esperanto, adjectives must "agree with" their nouns - that means that if a noun is plural, then an adjective that describes it must also be plural. Although in English, we say "red apple" or "red apples", in Esperanto, the word "red" has a plural form, used when "apples" is plural. »

Adjective (Adjektivo)

An adjective describes a noun. An adjective answers the question "What kind is (he/she/it)?" For example: "pretty", "good", "long" and "big". »

Verb (Verbo)

A verb presents an action or a state. Verbs answer the question "To do what?", "What is happening?", "What (are you/is he/are they) doing?" For example: "to sing", "stands", and "was". »

Adverb (Adverbo)

Adverbs describe a verb, an adjective, an adverb, or a whole phrase or sentence. Examples of adverbs: "beautifully", "shortly", and "yesterday". In English, adverbs often end in -ly. »

Preposition (Prepozicio)

A preposition is a small word that shows what role a phrase plays in a sentence. For example: "on", "in" and "under" »

Pronoun (Pronomo)

Pronouns are the words: I, you, she, he, it, us, they, one, himself/herself/itself. »

Affix, Prefix, Suffix (Afikso, Prefikso, Sufikso)

An affix is used to make compound words. Affixes, that are put after other roots, are called suffixes. Affixes, that are put before other roots, are called prefixes. »

Subject (Subjekto)

A subject is the primary word of a sentence, that is grammatically independant of the other parts of a sentence. Usually (but not always) the subject is the thing that performs the action in a sentence. For example, in the sentence "I love you", "I" is the subject. »

Object (Objekto)

An object is the thing that is directly affected by the action in a sentence. For example, in the sentence "I love you," "you" is the object. »