So I'm working through Makino and Tsutsui's Dictionary of Advanced Japanese Grammar, and I came across this sentence:
ソウルにいるのも今夜きりです。
This is my last night left in Seoul.
The entry is about teaching きり, which I understand just fine. What I can't work out is how も is being used here. 'Being in Seoul'も'This is the last night'. I can't see how this can mean 'even' or 'also' or any other definition I've looked at. I was thinking it must be a typo for もう, which would make sense.
This is what 庭三郎 calls the 「詠嘆のモ」, "the exclamation も".
その他に、「詠嘆のモ」と言われる用法があります。
巨人も弱くなったねえ。
この場合、他にも弱くなったチームがあって（例えば阪神）、それと同じよ うに、というわけではありません。たんにそのＮについて、述語が表す内容が 起こったことを（軽く）詠嘆的に述べているだけです。
俺も年をとったなあ。
あんたも馬鹿だねえ。
秋もようやく深まって、・・・
http://www.geocities.jp/niwasaburoo/18fukujosi.html
The nuance here is something like "This is my last night in Seoul" (and I'm emotional about that).
This is a bit confusing because it basically means the も particle has a usage that is completely opposite of what you've thought it means since you started learning Japanese. A good way to tell this usage of も apart is if the "also" meaning doesn't seem to make sense in context. Amateur translators will often force an "also" into their translation when faced with this unfamiliar usage because they feel uncomfortable interpreting noun + も as meaning anything other than "also".
I listed up several examples that I can use ‘も.’ in the sentence, but I cannot think up how I should incorporate the nuance of ‘も’ into English.
Even if I omit ‘も,’ from the following examples, you can understand or guess what I mean, but they sound sometimes awkward without “も.”
冗談も程々に - Refrain from joking.
今にも雨が降り出しそうだ - It’s going to start raining right now.
雨も上がった。さあ出かけよう - It stopped raining. Now let's go out.
桜も今週いっぱいだ - Full bloom of cherries will end by this weekend.
試験も終わった。これで羽を伸ばせる - The exam is over. Now I can fully go on the loose.
ローマも見[納]{おさ}めだ - This is the last time I see Rome.
君との付き合いもこれで終わりだ - (All done.) I have to break off our relationship.
明日にもここを発たねばならない - I have to leave here tomorrow.
いかにもあなたの[仰]{おっしゃ}るとおりです - True, you are exactly right.
100万円も使い道がない - Though I have ¥1 million, I don’t find the right way to use it.
Among the above examples, there's no problem to replace 冗談も with 冗談は, 桜も with 桜は, 試験も with 試験は, ローマも with ローマは, 君との付き合いも with 君との付き合いは, 明日にも with 明日には, and there wouldn't be much difference in meaning between two different ways of saying.
As I’m not a grammarian, I’m unable to explain logically what the functions and definition of “も” are. I’m sure somebody else can. But it seems to me “も“ is used to emphasize the preceding noun, adverb, i.e., words such as 冗談、今、雨、桜、試験、ローマ、付き合い、明日、いかに、and 100万円, like say, "this very" in English.
While も typically does indicate the presence of something else in the sense of "also", I believe sometimes it is used in a more general sense such that there is nothing to really compare against.
A found a description in the dictionary to back this up:
(3) 夜もふけてきた
...
...また、例文(3)のように同類の事柄が特定できない場合もある...
...[Also, as in example sentence #3 there are cases where the similar matter cannot be identified]
(English translation above is my own)
I have seen this usage in other expressions such as ”幸いにも” and ”というのも”.
Also, in certain cases も seems like it can be used to emphasize something, such as "百年も前”, where there is no sense of "also".
I'm pretty sure the usage of も in the poster's question applies in one of these categories, such that there is no feeling of "also" and possibly some level of emphasis.
This is a bit challenging to translate into English. It doesn't really mean "this is also my last night in Seoul" (as opposed to something else that might be his/her last night in Seoul), but rather "'being in Seoul' also comes to an end (for me) tonight".
What the other thing also coming to an end tonight is, is a mystery without context.
Try the following:
朴さんに会えるのは今夜きりです。
ソウルにいるのも今夜きりです。
The other possibility, which deviates slightly from the other answers, is that there is something else that comes to an end tonight (as there are an indefinite number of possibilities), but nothing specific has to be mentioned in the context.
Consider the following translation for the same phrase:
Among other things, being in Seoul comes to an end for me tonight.
Just as in English, "among other things" can be omitted and essentially keep the meaning unchanged.
It might help to grasp the meaning by replacing the "も" with "は" or "が". Then it's just a nominalized verb "いる" being described.
