Answer: The way to write the sentence: "The store was freezin" as an absolute frase would be: The store freezing, we need to leave it quickly. Or We need to leave quickly, the store freezing.
An absolute phrase consists on a phrase that modifies a noun in a sentence, but it is not connected to the sentence by a conjunction. It is separated with a comma only, and it could be removed from the sentence without changing the meaning of the sentence. An absolute phrase tends to contain a participial.
I hope i helped!! <3