Question

What type of language convention has the author used to separate the declarative sentence from the disruptive phrase in this excerpt from "Totally like whatever, you know?"? "Declarative sentences—so—called because they used to, like, DECLARE things to be true, okay, as opposed to other things are, like, totally, you know, not— have been infected by a totally hip and tragically cool interrogative tone?" Commas Question mark Capitalization Em dashes

Answer 1

The language convention that the author used to separate the declarative sentence from the disruptive phrase in this excerpt are em dashes.
The disruptive phrase is everything separated from the rest of the sentence by these dashes - "so called because they used to, like, declare things to be true, okay, as opposed to other things are, like, totally, you know, not." This phrase disrupts the natural flow of the sentence by being randomly embedded in it.