Gender and Number
Number is not generally a problem for English speakers. We say <<one student, two students>> and add an -s to student-s to obtain the plural. The concept of number, then, is one that we share with Spanish speakers.
Number, in its more familiar forms, is referred to as singular and plural. Thus, in Spanish, we make a noun plural by adding an -s if the noun ends in a vowel and -es if it ends in a consonant:
alumno / singular / one student; alumno+s = alumnos / plural / more than one student; ciudad / singular / one city; ciudades / plural / more than one city; profesor / singular / one [male] professor; profesores / plural / more than one [male] professor; profesora / singular / one [female] professor; profesoras / plural / more than one [female] professor.
The indefinite article un is also a number. Thus un alumno can mean a student or it can mean one student. The context usually makes this clear.
However, in Spanish, the indefinite article can be singular un or plural unos. Thus, un alumno means a student or one student, while unos alumnos means some students. How many exactly? We don't know: the articles is indefinite and some students is an indefinite number.
In English, the concept of gender appears to be clear. There are two genders: masculine and feminine. A man is masculine; a woman is feminine. However, where a man and a woman differ in their gender, they do not, in English, differ in their indefinite article: a man, a woman.
Spanish, on the other hand, like French, offers different articles for different genders and the noun and the article must agree both in gender and in number.
A man = un hombre; a woman = una mujer; some men = unos hombres; some women = unas mujeres.
This also applies to a word like student / alumno. In this fashion we have un alumno / una alumna / unos alumnos / unas alumnas; here the gender and the number of the students are indicated clearly by both the noun ending (-o, -os, -a, -as) and the ending of the indefinite article (-o, -os, -a, -as).
Where Spanish and French differ from English is that in Spanish, for example, all nouns are given a gender, not just nouns that refer directly to people with gender. Thus, la casa / the house is feminine; el libro / the book is masculine.
How do we know what gender is given to an inanimate object? Initially we don't. However, if we speak French, then we can be sure that the gender of nouns is usually the same in French as in Spanish. If we speak English, we have to remember the gender of the nouns. What is the easiest way to do this? Learn the noun and the article together: la casa / the house, la mano / the hand, el día / the day, el libro / the book.
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