I need some help with Spanish vocabulary?

is not estan son monedas is (estas son monedas). When you use estos is because the subject is male for example the tree, which is el arbol. "El" is masculine as you probably know by now. If it was singular it will be "Este Arbol" or this tree. Estos is more use for plural. La moneda or the coin is female which is why you use "Estas" for plural and Esta for singular. Estan is more like they are, for example: "Las monedas estan en la mesa" or the coins are on the table. A way to tell the difference from female and male is that the male nouns ends with the sound of "O" eig: Arbol, Caballo, Mano, Dedo and the female nouns ends with the sound "A" eig: Moneda, Casa, Amiga, Mesa. I hope my explanation helps.

They are dependent on the noun they are describing. If the noun (i.e. arboles) is masculine and plural, then the adjective must match. So actually it should say Estes son arboles, and Estas son monedas. I don't know why it is teaching you badly. Esto and estos are neutral gender adjectives, so it would be if you didn't know what it was, and couldn't give it gender until you knew the name.

Este-singular masc.

Esta-singular fem.

estos-plural neut

estas-plural fem

and I don't know why estan is there.

NOW, on another topic but similar.....

There are verbs that have the same letters, but with accents. I can't produce accents on this forum, but I'll tell you where they are. The verb "estar" means "to be," and the conjugations in present tense are similar to these adjectives you asked about. All of the verbs below have an accent over the a, except for the "nosotros" form.

Yo estoy

Tu estas

El esta, Ella esta, Usted esta

Nosotros estamos

Ellos estan, Ellas estan, Ustedes estan

This form of "to be" is not to be confused with "ser," which means "to be," as well. It is very difficult to explain to a beginner learner in Spanish, but the "estar" form is more temporary, and is used as a linking verb with descriptions of things that can change, or locations that can change. "Ser" is used for more permanent descriptions.

Okay, so este is neutral. Esta is feminine, because it ends in a, like most feminine words. esto is masculine, so it ends in o like most masculine words. But just because a word ends in o or a doesn't mean it is always masculine or feminine, such as in cases like el idioma, el mapa, etc.

Estan is not a word, Están is a conjugation of the verb estar that means "(they) are." Estos and estas are plural, you you wouls say estas monedas, and estos arboles.

Also, Está a conjugation of the same verb, estar, and that means (it) is.

So be careful with thouse.

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