rajinikanth Wrote:1) to me it seems "researchers have discovered" seems to modify the place.
Should it be, a fact that the researchers have discovered. I understand its in the non underlined section but would like to learn the grammar if possible
no, this is a special type of modifier that actually doesn't really have ANY effect on the surrounding sentence. it imposes no restrictions whatsoever, whether on tense, singular/plural, or anything else.
the same is true when similar types of things come at the beginning of sentences:
researchers have found that...
studies have shown that...
my friend said that...etc.
the difference is this:
when the modifier comes in the middle of the sentence, you don't need to use the word "that" anymore (note that this modifier just says "researchers have discovered").
if i were you, i would just memorize this sort of modifier separately from other modifiers.
i would do so especially because, unlike almost all other modifiers, this one can go basically anywhere at all in the sentence (as long as you are not interrupting constructions that are supposed to be in one piece).
2) is this correct "and tends not to bother to recover a perishable treat"
whats the role of "recovering" here as in with respect to tense?
-ING forms aren't verbs, and so don't have a tense of their own. they just adopt the tense of the surrounding clause.
in this case, provided this problem is from a reputable official source, you can take this as proof that "to bother VERBing" is a legitimate idiomatic structure.
in fact, this may be another case in which there are two legitimate structures, but the test goes for the one that gets rid of undesirable repetition.
note that your suggested alternative contains "to" twice in the space of three words: "to bother to recover". that's considered "ugly" -- see here:
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