Q1 -- "it" is that indefinite pronoun that's often used in English (without an antecedent).
Q2 -- Let's rephrase so it's a sentence instead of a question:
It is how much to take the subway.
I'd say "to take the subway" is an infinitive phrase that is adverbial, modifying "much."
I'm not 100% sure, though. These colloquial phrasings aren't always able to be analyzed well!
Q3 -- Possible answers:
"It's fifty cents."
"Fifty cents"
"A monthly pass costs $30."
1. How much is it to take the subway?
2. Answer:________________________.
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Q1: In #1 what does 'it' refer to?
Q2: What does 'to take the subway' modify? Is 'to take the subway' a noun phrase or an adverbial phrase?
Q3: What is the suitable answer to the question 1?
2 answers
I don't know if you'll come back to see this, but I'll post the explanation anyway. I asked a friend of mine what she thought the infinitive phrase is doing in this question:
How much is it to take the subway?
She says she believes "to take the subway" is serving as an appositive to "it" -- and that makes it a noun phrase.
I believe she's right!
How much is it to take the subway?
She says she believes "to take the subway" is serving as an appositive to "it" -- and that makes it a noun phrase.
I believe she's right!