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第15課: Adjectival Nouns I　形容動詞①

Vocabulary Notes:

①Taisetsu 大切,  jūyō 重要, and daiji 大事 can all translate as "important," but they are not exactly the same.
・Taisetsu 大切  refers to something that's important in the sense that if the thing in question were lost, there would be harm felt on an emotional level. 
・ Jūyō 重要 refers to objective importance. 
・Daiji 大事 refers to things/people you take special care to; it/they're important to you. Or, it may be used as a noun meaning "serious matter/crisis." 

25. 月は綺麗でした。
Tsuki wa kirei-deshita.
The moon was pretty.

26. 大切だった人
Taisetsu-datta hito
A person who was indispensable/important

27. 英語能力が重要でした。
Eigo nōryoku ga jūyō-deshita.

English proficiency was important.

28. まさに大事だった。
Masa ni daiji(-)datta.
It was a serious matter, exactly.

Because we have already learned how the copula is conjugated, we will not be revisiting how each possible negative form is made. Instead, the chart below lists off the possible forms from least to most polite. Just remember the general observation that contractions are less formal. 

Vocabulary Notes:

① Yūshū 優秀 refers to someone's skill(s) being exceptional. 

② Hontō 本当 can also mean "really" and may be used as a noun, adjective, or an adverb. It can also translate as "true" or "genuine." 

29. この気持ちは変じゃない。
Kono kimochi wa hen-ja-nai.
This/these feeling(s) is/are not strange.

30. あれはもはや重要ではない。
Are wa mohaya jūyō-de-wa-nai.
That is no longer important.

31. あの人は優秀じゃありません。
Ano hito wa yūshū-ja-arimasen.
That person isn’t excellent/superb. 

Because the plain and polite negative-past forms of adjectival nouns utilize the copula, we will forego an etymological breakdown. Instead, the recap chart below will list variations from least to most polite. We will also forego discussing why the polite forms can't be used as attributes as the reasoning is the same as before.

Some educators erroneously state that all adjectival nouns arose due to Chinese influence. Although it is true that most are Sino-Japanese in origin, native adjectival nouns have always existed.

Sometimes, an adjectival noun form is made by dropping /i/ and just using the stem, but most are made by following the stem with the suffixes -ka か, -raka らか, or-yaka やか. The difference in nuance is usually that the adjectival noun form(s) are more abstract, intangible, and/or refined. 

Vocabulary Notes:

①Atarimae 当たり前 comes from a misspelling of tōzen 当然. The two words are interchangeable. 

②The word etchi エッチ, often simply spelled as Ｈ,  comes from the "H" in the romanized spelling of hentai 変態, an all too familiar word to many because of its meaning of "pervert."

43. トレーニングが必要なことも稀ではありません。
Torēningu ga hitsuyō-na koto wa mare-de-wa-arimasen.
It is also not rare for training to be necessary.

44. 当たり前が当たり前じゃなかったことに気づいた。
Atarimae ga atarimae-ja-nakatta koto ni kizuita.
I realized that what was/the "obvious" wasn't obvious.

Grammar Note: In this sentence atarimae 当たり前's dual nature as either a noun or adjectival noun is on full display. The use of koto こと to make the preceding phrase a noun also highlights how any basic plain speech conjugation (past, negative, negative-past) can modify a noun in return. 

A small handful of adjectival nouns come from loanwords. Sometimes, their meanings will be different from what they were in the original language. Some may even be used without -na な at all if it a part of a phrase borrowed verbatim.