The answer to your question is deepest
“ Sometimes people say silly things. They do not intend to be mean.”
It's a restrictive clause. All restrictive clause can't be in between a punctuation (i.e: a comma) and it will always have a pronoun "THAT".
So based on "A Defence of Poetry" by Shelly, in which Shelly suggests that emotions experienced in life are constantly changing, the lines from "Mutability" that can also be seen as a reflection of this idea would be these:"like forgotten lyres, whose dissonant strings / Give various response to each varying blast, / To whose frail frame no second motion brings / One mood or modulation like the last.”
