grammarprepositions
I have followed a few discussions about whether "on lunch", as opposed to "at lunch", is correct.
One opinion stated that "on lunch" indicates a status (on leave, on break) while "at lunch" is more likely conveying a sense of a person eating in a physical location.
Thus, I do not know whether "on lunch" is grammatically correct or it is just an informal, shortened version for "on lunch break".
Neither sentence is correct. Each needs 'for' or 'about' - we care for/about people. In my opinion, 'give' is more natural for most native speakers than 'gift'. It is certainly far more common.
Give this to the people for/about whom you truly care. Very formal.
Give this to the people who you truly care for/about. Less formal, but acceptable these days in all but the most formal of situations.
Give this to the people whom you truly care for/about. A mix of the formal and informal that is best avoided. "Because whom is unusual in an informal style, it is very rare in clauses that end with prepositions." Michael Swan (2005.452), Practical English Usage.
This is an example where it's not a matter of one preposition being right while the other is wrong. Either preposition would form a grammatical sentence.
To understand why, it's important to note that the word lunch can be used as a noun or as a verb:
Therefore, in this sentence:
I went to the mall to meet my parents to lunch.
the phrase to lunch is being used as an infinitive, while in this sentence:
I went to the mall to meet my parents for lunch.
the word lunch is being used as a noun.
Though both are grammatical, most of the time, I would recommend using for, not to. Using lunch as verb often sounds rather stilted, particularly at the end of a sentence like in this case.
Best Answer
For a work context:
To be on a break, to be on a lunch or tea break, but: to be at lunch.
In short, the guy's out of the office.