When do we use Quanti or Quante or Quanto etc.. Is there a rule we should know ?
From what I can tell, Quanta and Quanto are for feminine and masculine respectively and is the equivalent of "How much", i.e. "How much water" or "How much wine", i.e. for something that isn't "countable" or "discrete".
Quante and Quanti are the feminine and masculine for "How many", in other words "How many girls" would be "Quante ragazze" and "How many boys" would be "Quanti ragazzi".
Yup, they follow the same rules as the articles. Masc sing = -o; Fem sing = -a; Masc plural = -i; Fem pl = -e. When you're talking about quantities you use the singular endings for 'uncountable' nouns, in other words when you want a measurement or quantity not a number in reply (250g rice vs 3 tomatoes). Other words also change their endings in the same way like 'this' which is questo/questa/questi/queste etc
Okay, so in English terms it is the difference between "number" and "amount." When you would use the word "amount" in English you then use quanta/quanto and when you would use the word "number" it's quante/quanti. For example water... you wouldn't be able to ask "what number of water do you drink" but rather "what amount of water do you drink." And for people, it is grammatically correct to say "what number of women are coming?" rather than "what amount of women are coming?"
Or to clarify even further, it's the difference between "how many" and "how much." "How many women/men" - Quante/quanti donne/uomini. "How much water/wine" - Quanta/Quanto acqua/vino
Some confusion remains. I'll start with what we know.
Quant' "a / o" Singular. Measurable because it is singular. How much water, time, coffee, weight.
Feminine "a" :
Quanta aqua. Masculine "o" : Quanto tempo, Quanto caffè,
"e / i" Plural.
Countable because they are plural. How many girls, boys, cities, dogs.
Feminine "e" :
Masculine "i" : Quanti ragazzi,
When DL exercise requires selecting matching words "how many" ONLY matches with "i" Quanti.
Their matching exercises match the word "e" Quante with "how much" not with the feminine plural "how many."
My computer translator gives the following definitions.
Quanta = how much,
Quanto = how much, Quanti = how many. Quante = how much is it,
Quant'è = how much is it.
If you reverse translate (Quante = how much is it) the result will be Quanto è.
My translator will not recognize Quante as "how many" unless I specifically pair it with a feminine plural word.
DL's use of Quante has left me at a bit of a stumbling point. It appears that "Quant'è", "Quante", and "Quanto' è" are interchangeable when the meaning is "how much is it?"