Question

Por qué con algunos sustantivos femeninos como agua el artículo femenino la se transforma en el

Answer 1

El is the singular, masculine definite article (the word for "the"), while la is the feminine version. But there is one instance where el is used with feminine nouns.

The substitution of el for la takes place only when it comes immediately before a singular noun that begins with a stressed a- or ha-. A few examples:

el agua (the water)
el ama de casa (the housewife)
el asma (asthma)
el arca (the ark)
el hambre (hunger)
el hampa (the underworld)
el arpa (the harp)
el águila (the eagle)
Above is the basic rule, and if you understand it you need continue no further. What follows is merely additional explanation followed by a few exceptions.

All the nouns in the list of examples are feminine. If they are in plural form, las is used:

las amas de casa (the housewives)
las arcas (the arks)
If they are modified by adjectives that follow the noun, the regular rules apply to the adjectives:

el agua purificada (purified water)
el arpa paraguaya (the Paraguayan harp)
el hambre excesiva (excessive hunger)
If a word intervenes between the definite article and the noun, la is used:

la pura agua (pure water)
la insoportable hambre (the unbearable hunger)
la feliz ama de casa (the happy housewife)
la gran águila (the great eagle)
If the accent of the noun is not on the first syllable, the definite article la is used with singular feminine nouns when they begin with a- or ha-:

la habilidad (the skill)
la audiencia (the audience)
la asamblea (the meeting)
The substitution of el for la does not occur before adjectives that begin with a stressed a- or ha-, just nouns:

la alta muchacha (the tall girl)
la agria experiencia (the bitter experience)
There a very few exceptions to the rule that el substitutes for la immediately before a noun that begins with a stressed a- or ha-. Here are the major ones:

la árabe (the Arabic woman)
La Haya (The Hague)
la a (the letter A)
la hache (the letter H)
la haz (an uncommon word often meaning "face," not to be confused with el haz, which can mean "sheaf," "shaft" or "beam")
Note about un and una: Most educated writers change una to un under the same conditions where la is changed to el. Thus, it is common to see constructions such as these:

un águila (an eagle)
un ama de casa (a housewife)

Answer 2

thank you

Answer 3

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