This sentence is part of the abstract of a scientific article, which helps explains what I would consider overly florid (and somewhat pretentious) verbiage. Expressions like
This research contributes to filling a considerable gap ...
should be simplified to
This research fills a considerable gap ...
Or, if this sounds too presumptive, then something ...
To me the first implies there exists evidence that no eating has taken place: He is extremely skinny, showing the signs of starvation and malnurishment, etc.
The second implies that there is lack of evidence of him eating: There is no food in the fridge, no dirty dishes, no crumbs, no food scraps in the trash, etc.
Logically both come to the same ...
The usage of "To ..., [Independent Clause]" in this case is as follows:
The "To ... " portion tells the reader/listener what the speaker is about to do, or the aim of the Independent Clause. It describes the Independent Clause or the clause's function within a conversation.
In this case it is saying "Hey, I am about to use a Star Trek term so get ready ...
To borrow a phrase from the old Star Trek series, the "prime directive" of the limbic brain is to ensure our survival as a species.
You have explained that it is the preposition "to" at the beginning of this sentence that is confusing you.
It is quite common to introduce a clause with a phrase containing to followed by an infinitive, for example:
To be ...
In examples #2 and #3, the infinitive expresses purpose, and the placement is natural. Example #1 is different; studying in America would be the content of the opportunity but not its purpose. (Opportunities may serve purposes, but do they have purposes?)
It depends entirely on the context. For example, you could write
The technicians were fired to reduce the company's costs.
"The company" is not really the subject of the infinitive. The possessive is an adjective modifying "costs"
The passive tense already implies the subject is whoever employs the technicians. It's not necessary to explicitly ...
There's not really much difference between these sentences -- not when it comes to the information they actually convey, anyway. Today is my birthday, whether I say it happens to be, or just that it is.
Which brings us to the question of why a structure like this exists. Well, because language is an imprecise and constantly evolving tool and sometimes we ...
Essentially, no (they aren't different).
The phrase "happens" is used for saying that something is true, although it is surprising that it is true. Source You could similarly say:
Coincidentally, it's my birthday today.
Although it's worth noting that:
Coincidentally, it happens to be my birthday today.
Is also valid.
Interestingly, the phrase "it ...
I assume you may be confusing this with the indirect object in sentences such as
I ordered him to get me a drink.
I taught him to read Chinese
The verb "to report" does not take an indirect object like this. Instead "him" is the direct object, meaning the thing being reported. You have to use the preposition "to" to indicate the other party:
In the case of "I reported him to be safe", he is safe. "To be safe" is an adjectival phrase which modifies 'him'. You could say the same thing like this:
"I reported him safe."
That might look a little more ambiguous at first, but note that 'safe' is just an adjective--it is performing the exact same grammatical function as 'to be safe' in the original ...
I reported him to be safe.
means that the speaker has reported some other person (presumably identified in previous content) to be safe. It corresponds with example B in the question. A similar statement corresponding with example A would be:
I reported myself to be safe
I reported myself as safe
This could be shorten to "I reported myself ...
Unless it is a clumsy word-order swap on, 'Police claimed to have had the file sent', that sentence is not right.
The "have-had" combination is not a problem in some circumstances:
"I have had fish that wasn't quite fresh, and it was awful,"
"We have had to reconsider."
But in the past perfect verb tense we use either "have" or "had" (not both) ...
Her dying wish was for him to hike the Ap. trail.
Him hiking the Ap. trail was her entire dying wish. Her dying wish equaled him taking up the hike.
Her dying wish for him was to hike the Ap. trail.
She may have had many dying wishes for different people. The one she had for him was him doing the hike.