Sentence Correction

1)The fight over the speed limit, a measure regarded by opponents as ineffective and meddlesome and by supporters as a conserver of life and energy, continues in our legislatures and on our freeways.


the word continues after comma modifying which one - the fight or the speed limit?

the skeleton of the sentence is as follows :The fight over the speed limit,XYZ,continues in our legislatures and on our freeways.
so basically u can just ignore the thing in between the comma
as to ur doubt : "continues" is a verb of subject "the fight" .

He was going to Eton, his father's school, in the following autumn.


sentence after comma in the following autumn modifying which one - he was going to Eton or only Eton?

Soumita Ghosh wrote:He was going to Eton, his father's school, in the following autumn.


sentence after comma in the following autumn modifying which one - he was going to Eton or only Eton?

I'm not too sure what you're asking. "His fathers school" is an appositive phrase that renames the school, Eton. So in this case it looks like the prepositional phrase "in the following autumn" is modifying the noun Eton. Usually noun modifiers need to be placed next to the noun they modify but i think since there's an appositive phrase it's ok.

Soumita Ghosh wrote:He was going to Eton, his father's school, in the following autumn.


sentence after comma in the following autumn modifying which one - he was going to Eton or only Eton?

here the prep phrase "in the following autumn" is an adverb of time for the action "was going".

Hope this helps !!