1. It's very noisy here. 2. I can't stand it anymore.
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What does 'it' refer to in #1? What does 'it' refer to in #2? Are both refer to the same thing?
In #1, "It" is being used like "there" is sometimes used -- simply to introduce a sentence. Scroll down on both these webpages to see the explanations/examples for "it" --
http://learnenglishteens.britishcouncil.org/grammar-vocabulary/grammar-videos/there-there-are-and-it
and
http://learnenglish.britishcouncil.org/en/english-grammar/pronouns/it-and-there
In #2, "it" refers to the noisy surroundings in sentence #1.
In #1, 'it' refers to the noisy environment the person is in.
In #2, 'it' refers to the situation of being in a noisy environment.
While both sentences involve noise, 'it' in #1 specifically refers to the environment, while in #2 it refers to the overall situation. Therefore, they may not necessarily refer to the exact same thing, although they are related.
To determine what 'it' refers to in both sentences, we need to look at the context given.
In sentence #1, "It's very noisy here," the word 'it' most likely refers to the current environment or location the speaker is in. The use of the word 'here' suggests that the speaker is referring to the noisy surroundings.
In sentence #2, "I can't stand it anymore," without further context, it is unclear what 'it' specifically refers to. However, given that this sentence follows the statement about it being noisy, it is reasonable to assume that 'it' still refers to the noise or the noisy environment mentioned in the previous sentence.
Therefore, it is likely that both instances of 'it' refer to the same thing, which is the noise or the noisy surroundings.