Differences in meanings of interrogative words


Can someone please explain to me the differences between the following
interrogative type words?

  1. いくらか/いくつか

  2. いくらも/いくつも

  3. いくらでも/いくつでも

  4. いくら/いくつ/どのくらい (in questions)

For example I know that いくらか and いくつか both seem to mean "some..." or
"several..." but are they used in slightly different situations or are they
interchangeable? etc. etc.




I doubt いくらか/いくつか, いくらも/いくつも いくらでも/いくつでも should be called
["interrogatives."](https://en.wikipedia.org/wiki/Interrogative) They don't
make a interrogative sentence by themselves. いくらか = "some (uncountable)", いくつか
= "a few (countable)", いくらでも "no matter how many/much
(countable/uncountable)", いくつでも "no matter how many (countable)"

いくらも is slightly uncommon. I think it's mostly used together with ない
especially in literature, as in

> いくらも残ってない  
>  [we] don't have much left

On the other hand いくつも is very common, = "a lot of"

> [いくつものドアをノックした](http://j-lyric.net/artist/a001c0c/l006a58.html)

いくら _is_ an interrogative. It can either mean "how many" or "how much is the
price", but I think it increasingly means only the latter nowadays.

> このサバいくら？  
>  How much is this [slice of] mackerel?

On the other hand いくつ and Chinese-originated 何個(nanko) is taking the place as
an interrogative for number of items.

> いくつ/何個 必要ですか？  
>  How many do you need?

The notable usage of いくつ (not 何個) is asking the age of a person:

> 失礼ですが、お幾つですか？  
>  Forgive my rudeness [if you don't mind me asking], how old are you?

どのくらい is also an interrogative to ask "to what extent" "to what degree" or
"how intense." It's very versatile.

> このお肉、どのくらい焼けばいいですか？  
>  How long should I grill this piece of meat?
>
> あれからもうどのくらい経っただろうか  
>  How much time has passed since then

It can even mean "how much":

> この壁にはどのくらいのペンキがいるかな？  
>  How much of paint do we need for [covering] the wall?

