(1) As you know, native speakers woud have no problem with
either sentence and would pay no attention to the dangling
(2) Serious students such as you make us native speakers pay
more attention, and that's a good thing.
(3) Yes, it is only my opinion that your first sentence is correct.
In other words, "based on new evidence" modifies the noun
(4) Yes, it is only my opinion that you are 100% correct: the participle
in the second sentence is "dangling." That is, the investigators cannot
be based on new evidence.
(a) After checking some sources, I have come to the conclusion that
maybe (maybe) there are three ways to rewrite it in "good" English:
(i) Because of new evidence, investigators will reopen the case.
(ii) Based on new evidence, the case will be reopened by investigators.
(iii) The investigators' decision to reopen the case is based on new
evidence. / The investigators' reopening of the case is based on new
(a) In (iii), I learned a wonderful phrase that you may be interested in:
"phantom noun." That is, I had to find a noun for "based on new
evidence" to modify.
***** Thank you for your question *****
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