Yes, 1-3 all mean the same thing. In 3, "lunch" is used as the object of the preposition "of" -- an adverbial prepositional phrase modifying the phrasal verb "take out."
And yes, 4-10 all mean approximately the same thing. There are a couple of even more casual expressions I can think of!
Long time, no see!
It's been ages!
1. Lunch is on me.
2. I'll buy you lunch.
3. I'll take you out to lunch.
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Are they all the same in meaning? Is 'lunch' in #3 used as a verb?
4. Long time no see.
5. It's been a long time.
6. I haven't seen you in ages.
7. It's been so long.
8. I haven't seen you for a long time.
9. It's been a long time since I saw you last.
10. I haven't seen you for a while.
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Are they all the same in meaning? Do you have some more similar expressions?
2 answers
In 3, "lunch" is used as the object of the preposition "to" -- an adverbial prepositional phrase modifying the phrasal verb "take out."
("to" not "of"!)
("to" not "of"!)