Demasiado: Too, too much, too many.
Demasiado is a word that we use a lot, but sometimes it means "too much" and other times, "too many". How the hell do I know how to say what I want to say then?
Too...
This is focused on a quality. Too loud, too far away, too naive...
Demasiado + adjective (describing word)
Demasiado doesn't change because it doesn't refer to a noun, the adjective does.
Ex:
Lara es demasiado nostálgica - Lara is too nostalgic.
Somos demasiado bajos para ese juego - We're too short for that game.
Pienso que Rodrigo es demasiado generoso - I think Rodrigo is too generous.
TO DO something too much
Demasiado + verb
Demasiado doesn't change at all, because verbs don't have gender or number per se, so demasiado always stays in its neutral, masculine singular version.
Examples:
Tu hermana habla demasiado - Your sister talks too much.
Te preocupas demasiado - You worry too much
¿No trabajas demasiado? - Don't you work too much?
No es bueno enfadarse demasiado - It's not good to get angry too much.
Amount
Too much of something
Demasiado or demasiada + noun
You choose the masculine or the feminine version, depending on the gender of the noun.
Too many of something
Demasiados or demasiadas +noun
You also choose between masculine and feminine, and in this case you're also using the plural (adding an -s at the end).
Ex:
Tenemos demasiadas cosas - We have too many things.
El coche hace demasiado ruido - The car makes too much noise.
Hay demasiada comida - There is too much food.
Pablo alimenta a demasiados gatos - Pablo feeds too many cats.
Practice
Fill in the gaps with:
demasiado, demasiada, demasiados or demasiadas
¡Corres ______________! - You run too much!
¿No está ____________ alto? - Isn't it too loud?
No tenemos __________ dinero. - We don't have too much money.
Nunca puedes aprender ___________. - You can never learn too much.
Hay _________ niños en el parque. - There are too many kids in the park.
A veces, son ___________ infantiles - Sometimes, they're too childish.
Ella tiene ___________ ropa - She has too many clothes.
Él se queja ____________ -He complains too much.
Son _____________ flores (femenine), no cabrán - They're too many flowers, they won't fit.
Sol: demasiado/demasiado/demasiado/demasiado/demasiados/demasiado/demasiada/demasiado/demasiadas
Hope that helped!
¡Hasta pronto!