“Life can only” “be understood” “backwards”
vs.
“But it” “must be” “lived forwards”
If you can’t see how that’s inconsistently formatted then I don’t know if an in-depth grammatical analysis will help you, so I’ll just point out that one is “3 words” “2 words” “1 word” and the other is “2 words” “2 words” “2 words”
Beyond that, look at the position of the subject and the modal, the “be” and the main verb, and the directional adverb.
It matches the speaker: The man is going backwards, the dog is going forward.
I get that part, but it doesn’t match.
“Life can only” “be understood” “backwards”
vs.
“But it” “must be” “lived forwards”
If you can’t see how that’s inconsistently formatted then I don’t know if an in-depth grammatical analysis will help you, so I’ll just point out that one is “3 words” “2 words” “1 word” and the other is “2 words” “2 words” “2 words”
Beyond that, look at the position of the subject and the modal, the “be” and the main verb, and the directional adverb.
It’s inconsistent formatting.
The dog is trying its best OK