Translation guide
The English adverb "deeply" is used to express intensity, profundity, or physical depth. In Japanese, there is no single direct equivalent; the translation depends on the specific meaning and context. This guide covers common ways to express "deeply" in Japanese, organized by intended meaning.
To express that an emotion, feeling, or state is felt or experienced to a great degree.
The adverb 深く (fukaku) is the most direct translation and is used with verbs of emotion or thought, such as 感動する (to be moved), 感謝する (to be grateful), 悲しむ (to grieve), etc.
彼の言葉に深く感動した。
I was deeply moved by his words.
I am deeply grateful for your support.
In casual speech, とても (totemo) meaning 'very' can often replace 'deeply' when modifying adjectives or adverbs, though it lacks the nuance of depth.
その話を聞いて、とても悲しくなった。
Hearing that story, I became deeply sad.
心から (kokoro kara) literally 'from the heart', conveys sincerity and depth of feeling, often used with verbs like 感謝する, 謝る (apologize), 愛する (love).
心からお詫び申し上げます。
I deeply apologize.
つくづく (tsukuzuku) is used with verbs like 思う (think), 感じる (feel), 嫌になる (get disgusted) to express a deep, often reflective or weary realization.
つくづく自分の愚かさを思い知った。
I deeply realized my own foolishness.
To describe something going far down or far into something, either physically or metaphorically (e.g., deeply rooted, deeply involved).
Again, 深く (fukaku) is used with verbs like 掘る (dig), 沈む (sink), 入り込む (go deep into), 根ざす (be rooted).
彼は深く穴を掘った。
He dug a hole deeply.
その習慣は地域に深く根ざしている。
The custom is deeply rooted in the region.
When modifying a noun, the adjective 深い (fukai) is used, e.g., 深い眠り (deep sleep), 深い関係 (deep relationship).
彼は深い眠りについた。
He fell into a deep sleep.
To express that an action is done with thoroughness or careful consideration.
よく (yoku) meaning 'well' or 'thoroughly' is the most natural way to say 'think deeply' or 'consider deeply' in Japanese. 深く考える is also possible but can sound slightly more formal or literal.
よく考えてから決めてください。
Please think deeply before deciding.
This is a more literal translation, acceptable but less common in casual speech than よく考える.
その問題について深く考えた。
I thought deeply about the problem.
A formal term meaning 'to deliberate' or 'ponder deeply', used in written or formal contexts.
熟考の末、その提案を受け入れた。
After deeply considering, I accepted the proposal.
To describe a physical action done with depth, such as breathing or sighing.
Used with verbs like 呼吸する (breathe), 息を吸う (inhale), ため息をつく (sigh).
深く息を吸ってください。
Please breathe deeply.
彼は深くため息をついた。
He sighed deeply.
English often uses 'deeply' with adjectives (deeply concerned, deeply religious). In Japanese, this is usually expressed with adverbs like とても, 非常に, or by using the adjective's adverbial form + verb, rather than 深く. For example, 'deeply concerned' is 非常に心配している, not 深く心配している.
深い is an adjective modifying nouns, while 深く is the adverbial form modifying verbs. Choose based on what you are describing.
彼女は彼の言葉に深く傷ついた。
She was deeply hurt by his remarks.
この問題についてよく考える必要がある。
We need to think deeply about this issue.