As it is too noisy, I can't hear you.

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In this sentence, what does 'it' refer to?•English - Ms. Sue, Friday, December 25, 2015 at 5:45pm
In this kind of construction, "it" represents an understood concept. Wherever the speaker may be is too noisy.
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* As it is too noisy, I can't hear you.*

Thank you for your help. In this case, because there is no context, is 'it' an impersonal pronoun without referring to anything?

"It" is an indefinite pronoun. Of course, there's a context. We assume the listener knows why the speaker claims the noisy conditions.

Thank you.

e.g. I don't like that restaurant because it's too noisy.

(In this sentence, 'it' refers to 'that restaurant.' Am I right?)

e.g. There must be a fight going on outside. It is way too noisy.
(In this sentence, does 'it' refer to 'a fight'?)

Yes, to both of your questions.

In the sentence "As it is too noisy, I can't hear you," the word "it" is used as an impersonal pronoun. In this case, "it" does not refer to anything specific, but rather represents an understood concept. The speaker is using "it" to refer to the general situation of the noise being too loud, without mentioning any specific source of the noise. So, in this context, "it" is serving as a placeholder for the general concept of noise being too loud.