In a text, how to tell the difference between a date (of the year) and days/months?

Question

Seeing, for exampe, 4月から (or まで）in a text, how to tell if it means 'since April' or '4 months ago'　（respectively, 'until April' or 'after 4 months) ?

Similarly, how to tell if 4日から (or まで） means 'since the 4th this month' or '4 days ago' （respectively, 'until the 4th this month' or 'after 4 days)?

Answer 1

These will almost always mean "since April/the 4th" (I can't think of an example where they wouldn't).

• From 4 months ago　→　[４ヶ月前]{よん・か・げつ・まえ}から
• 4 months later　→　[４ヶ月後]{よん・か・げつ・ご}
• Since April　→　[4月]{し・がつ}から
• Until 4 months from now　→　[４ヶ月後]{よん・か・げつ・ご}まで

​

• From 4 days ago　→　[４日前]{よっか・まえ}から
• 4 days later　→　[４日後]{よっか・ご}
• Since the 4th of the month　→　[4日]{よっか}から
• Until 4 days from now　→　[4日後]{よっか・ご}まで

Answer 2

• [４ヶ月前]{よん・か・げつ・まえ}から　⇔　From 4 months ago
• [４月]{し・がつ}から　⇔　 From April
• [４日前]{よっかまえ}から 　⇔　From 4 days ago
• [今月４日]{こんげつよっか}から　⇔　From the 4th of this month

Time interval for months is indicated by adding the character "ヶ” (pronounced ka) before 月.　

The small ke (ヶ) is a Japanese character, typographically a small form of the katakana character ケ ke.　While identical in shape to a small ケ, the shape is actually an abbreviation for the kanji 箇 [more at Wikipedia, Small ke ]

Etymology: 箇/個/个 is a counter used sometimes in Chinese coming before the object, but in Japanese is only used before the object for counting months, and in other cases where it is used, it always comes after, e.g.,

• Japanese [４ヶ月]{よん・か・げつ}, c.f. ４个月 (Simplified Ch.), ４個月 (Traditional Ch.)
  • unique instance where Japanese borrows Chinese pre position 個 counter regular expression:
  • {number}{counter(noun)}{noun}
• Japanese [一人]{ひとり}, c.f. 一個人 (Traditional Ch.) or 一个人 (Simplified Ch.) -
  • unique case (including [一人前]{いち・にん・まえ}) of native Japanese post position counter regular expression:
  • {number}{counter(noun)}
• Japanese [一日間]{いち・にち・かん}, c.f. 一天 (Traditional+Simplified Ch. - no counter!)
  • usual case of native Japanese post position counter regular expression:
  • {noun}{number}{counter(noun)}

Note: I don't have a reference to show that the first two cases above described as "unique" are actually unique. If someone knows a reference or a counter example, please post.