"The four boys drank water."
Translation:Los cuatro niños bebieron agua.
Niños are boys. Muchachos are guys. Just a slight difference in age implied there. Also there's not enough context to use the imperfect form of beber instead of preterite so I wouldn't say "bebían" is accurate.
why don't you use 'el agua' here? I thought you always have to link a preposition to the noun?!
Same reason why the English sentence doesn't have the water either. Articles in Spanish are a complicated matter, in this case, the verb (beber / tomar) doesn't require its object to use an article.
Rules for numbers? Is cuatro grammatically an adjective here? Yet numbers don't change form? Unos/unas = some, is a different part of speech?
The only numbers that change gender are the number 1 and numbers from 200 to 999.
Un hombre / una mujer
Doscientos hombres / doscientas mujeres (200)
Novecientos noventa y nueve hombres / novecientas noventa y nueve mujeres (999).
so you have to take away the o in tercero when it's in front of a masculine noun but cuatro don't have to? is it just tercero or?
Tercero means third, while cuatro means four, I guess you meant cuarto (fourth), and no, it doesn't lose the o.
Btw, it also happens with primero (first), it loses the o when you put it before a masculine noun, as in, primer hijo.
Yes this female voice is so bad I have to guess a lot of words that she says and play her like five times until I can actually hear her correctly
Could someone explain why "El cuatro niños" was marked wrong? How do you know when to use "los" instead of "el"?
Yes. The word "el" is for singular, masculine nouns. The word "la" is for singular, feminine nouns. "Los" is the plural of "el" while "las" is the plural of "la".
El niño / el bolígrafo Los niños / los bolígrafos La niña / la falda Las niñas / las faldas
Does that help? :)