〜であろう (~de arō) — it is likely that ~ (written)

The most formal written 「だろう」— how reports, news commentary and essays predict.

Formula (सूत्र ढाँचा)

N／な-adj N／な-adj + であろう

Verb／い-adj V普通形／い-adj + であろう

Grammar rule (व्याकरण नियम र परिभाषा)

When to use it

In NHK news commentary, a government report or a long newspaper article you read predictions like 「外国人労働者は今後も増えるであろう」— 'the number of foreign workers will likely keep rising.'

Meaning

The meaning is the 「だろう」・「でしょう」you already know: 'probably.'
That is why it often comes with 「おそらく」「いずれ」「やがて」, and you also see it for guesses about the past: 「〜たであろう」(小さかったであろう = would probably have been smaller).

How to attach

After a noun or な-adjective, 「であろう」replaces 「だ」(想像以上であろう); after a verb or い-adjective, add it straight to the plain form (減るであろう・小さかったであろう) — no 「の」needed.

Versus what you know

The difference is only the clothes — 「でしょう」is polite speech (the weather forecast's 「雨でしょう」), 「だろう」is plain, and 「であろう」is the stiffest, written one; the writer sounds like they are calmly predicting from facts and reasoning.

Watch out

Careful: 「〜であろうと」from an earlier lesson (社長であろうと = even if it's the president) is a different form — add 「と」and it means 'even if.'
The key rule: 「であろう」is never used to ask someone or seek their agreement — saying 「君も来るであろう？」to a friend is comic; there it is 「来るでしょう？」or 「来るよね？」.

Examples (उदाहरणहरू)

人口が減り続ければ、地方のバス路線はさらに減るであろう。

じんこうがへりつづければ、ちほうのバスろせんはさらにへるであろう。

If the population keeps falling, rural bus routes will likely be cut even further.

How it is built (कसरी बन्यो) 人口が減り続ければ = if the population keeps falling → 地方のバス路線 = rural bus routes → さらに減る = fall even further (plain form) → attach 「であろう」 directly = will probably fall (the report's guess).

言葉も分からない国で働き始めた彼らの苦労は、想像以上であろう。

ことばもわからないくにではたらきはじめたかれらのくろうは、そうぞういじょうであろう。

The hardship of those who started working in a country whose language they didn't even know is likely beyond imagining.

How it is built (कसरी बन्यो) 言葉も分からない国で働き始めた = who started working in a country whose language they don't even understand → 彼らの苦労は = their hardship → 想像以上 = beyond imagination (N) → 「であろう」 in place of 「だ」 = is probably even more (than you could imagine).

早く対策をとっていれば、被害はもっと小さかったであろう。

はやくたいさくをとっていれば、ひがいはもっとちいさかったであろう。

Had measures been taken sooner, the damage would probably have been smaller.

How it is built (कसरी बन्यो) 早く対策をとっていれば = if measures had been taken early → 被害は = the damage → もっと小さかった = was smaller (past い-adj) → 「であろう」= would probably have been smaller (a guess about the past).

Knowledge check (मिनी ज्ञान जाँच)

Question: 1/3

「おそらく、この技術は今後ますます重要に＿＿であろう。」— fill the blank.

💡 Hint: Just like before 「だろう」— the plain form.