It does not mean that I will disappear for 1 month.
It can be 30 days,
it can be a fortnight,
a few days,
a few hours,
and also a few minutes
or even a few seconds.
Long time ago, I said “See you next month” to a colleague at the end of a month, he asked me if I were taking any leave and when would I come back. I told him, I was going back on the next day because the next day is a new month.
At 31 Dec 1999, you can say, “see you next century“.
At 31 Dec of any year, you can say, “see you next year“.
At 28 Feb, 29 Feb, 30, or 31, you can say, “see you next month“.
To a friend who you may never meet again, you can say, “see you in the next life“, or “see you in another world (Heaven or the Pure land at the West may be)”.
1Malaysia
