1. “It was a serious distraction and threat to more meaningful reform efforts.”
Something is wrong with this sentence. To diagnose the problem, remove one of the noun phrases from the beginning of the sentence and determine whether the remaining statement is still correct, then replace it and remove the other one. “It was a serious threat to more meaningful reform efforts” is correct, but “It was a serious distraction to more meaningful reform efforts” is jarring because the preposition is not idiomatically appropriate. The noun phrases are supported by different prepositions, so they cannot share the word to; assign the correct preposition to each one: “It was a serious distraction from and threat to more meaningful reform efforts.”
Should the word threat be preceded by the article a to make it parallel with distraction? No, because serious applies to both nouns, and an additional article would isolate threat from the shared adjective. Also, the phrase “and threat to” appears to be parenthetical, but it’s not necessarily necessary to set it off by commas, parentheses, or em dashes.
However, enclosing it in parentheses suggests a whispering insinuation, and using em dashes would signal a provocative interjection, so the context might merit either parenthetical strategy. In either case, though, threat should be assigned a repetition of serious — “It was a serious distraction from (and a serious threat to) more meaningful reform efforts” — or a distinct adjective (“It was a serious distraction from — and a grave threat to — more meaningful reform efforts.”)
2. “Elected officials and activists representing forty-five environmental groups attended the event.”
When two or more nouns or noun phrases follow one or more adjectives (as in the previous example), the assumption is that the modifying word or words applies to each noun. In this case, however, the subject consists of the elements “elected officials” and “activists representing forty-five environmental groups” linked by a conjunction, not “elected officials (representing forty-five environmental groups)” and “(elected) activists representing forty-five environmental groups” joined by and. To clarify this distinction, recast the sentence: “Activists representing forty-five environmental groups, as well as elected officials, attended the event.”
3. “He has to be, if not the, one of the stupidest people in TV news.”
The basic statement here is “He has to be one of the stupidest people in TV news,” but the writer has failed in an attempt to suggest the superlative as well, awkwardly implying also that “he has to be the stupidest person in TV news.” (The superlative is the ultimate form of an adjective, more extreme than the basic form — stupid, in this case – and the comparative, stupider.)
But “if not the” collides with “one of the”; the unstated — and incorrect — complete thought is, “He has to be the stupidest people in TV news.” To smooth out this disjointed sentence, introduce the superlative first in a complete thought, and then retreat to the milder criticism in a following modifying phrase: “He has to be if not the stupidest person in TV news, then one of the stupidest.”
Note that a comma does not follow be, because doing so would imply that two commas are necessary to set “if not the stupidest person in TV news” off from the basic sentence “He has to be then one of the stupidest,” and that’s a faulty grammatical analysis. This sentence is constructed from a simple “if, then” foundation, so use a single comma to separate the two propositions.
4. “He kept a house there as well as homes in rural Oxfordshire, England, and Miami.”
This sentence implies that the subject kept three additional homes: one in Oxfordshire, one in England, and one in Miami. (It also incorrectly suggests that, as in the second example above, a single adjective applies to all nouns that follow.) What the writer meant, as we determine momentarily — which is one moment too late — is that one additional residence is located in Oxfordshire, England, and another is in Miami.
When one or more “city, state” or “city, nation” constructions are associated with a “city” reference, the sentence must be revised to clarify the hierarchy of referents. One solution is to distance the two objects with proprietary prepositions: “He kept a house there as well as homes in rural Oxfordshire, England, and in Miami.” Another, clearer choice is to do so but also place the simpler referent first: “He kept a house there as well as homes in Miami and in rural Oxfordshire, England.”
5. “The company was to be paid between $300 and $400 million.”
This “you know what I meant” bungle is inoffensive but incorrect, and should be corrected on principle because a similar but more egregiously ambiguous construction would definitely merit revision, so why be inconsistent and excuse one but not the other? The two figures in question are $300 million and $400 million, and for the sake of clarity, the first instance of million should not be elided: “The company was to be paid between $300 million and $400 million.”
The same principle applies if the range is separated by the word to: “The company was to be paid $300 million to $400 million.” However, when the sentence does not apply to orders of magnitude — “Compliance ranged from 50 to 75 percent” — the operative word need not be repeated, because no ambiguity about the relation of the first number to the second one exists.