mination of gender often seems arbitrary (although it can generally be explained).
In English, plurals are marked with the addition of an s; f.i. boy, boys--although there are a few exceptions, such as child/children, ox/oxen. In Spanish, nouns ending in a vowel form their plural by adding s, and those ending in a consonant by adding es; those ending in z change the z to c. Examples: el hijo/los hijos, la hija/las hijas, el lßpiz/los lßpices, la mujer/las mujeres.
In English, adjectives are not marked by gender or number: they are invariable. In Spanish, they do so agree; f.i. alto/altos/alta/altas. Thus, adjectives agree in gender and number with the noun or pronoun they modify.
In English limiting adjectives precede the nouns they modify; so do they in Spanish. However, descriptive adjectives generally follow the nouns they modify; f.i. Diez caballos negros / Ten black horses.
In English the indefinite article a(n) is not modified
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