であるFormal written is/are
である links a noun or na-adjective to a statement with the basic meaning “is” or “are.” It is mainly used in formal, impersonal writing rather than ordinary conversation.
Basic use
Use である when presenting facts, definitions, classifications, or conclusions in a formal explanatory style. It follows nouns and na-adjective stems directly.
Nouns and na-adjectives
この制度の目的は、地域の交流を促すことである。
The purpose of this system is to promote interaction within the community.
Analyzeこの手順は簡単である。
This procedure is simple.
Analyze簡単 is a na-adjective stem, so no な is inserted before である.
当時、最大の課題は資金不足であった。
At the time, the greatest challenge was a lack of funding.
Analyzeこの結果は偶然ではない。
This result is not a coincidence.
AnalyzeKeep the whole document consistent
In a report written in this style, nouns and na-adjectives take である, while verbs and i-adjectives normally use their plain forms. The style therefore applies to the whole passage; it is not an ending that must be added to every sentence.
A consistent report paragraph
本調査の目的は、利用者の傾向を明らかにすることである。回答者は二百名であった。結果は表一に示す。最も多かった回答は「価格」である。
The purpose of this survey is to clarify user trends. There were two hundred respondents. The results are shown in Table 1. The most common answer was “price.”
AnalyzeThe verb 示す remains in its plain form, which matches the surrounding formal plain style.
Formal does not mean polite
だ is the ordinary plain ending, and です is the ordinary polite ending used toward a listener. である instead selects a formal, impersonal style, especially in writing. It is more formal than either in its typical setting, but it is not more polite than です.
More examples
水は生命に不可欠な資源である。
Water is a resource essential to life.
Analyzeこの地域は冬でも比較的温暖である。
This region is relatively mild even in winter.
Analyze会議の主な目的は、今後の方針を決めることである。
The main purpose of the meeting is to decide future policy.
Analyze以前、この建物は市立図書館であった。
This building was formerly a municipal library.
Analyze両者の違いは決して小さなものではない。
The difference between the two is by no means small.
Analyze本日の議題は、今後の安全対策である。
Today’s agenda is future safety measures.
AnalyzeThis can sound natural in a prepared formal speech as well as in writing.