Translation guide
To examine or look into something in great detail, leaving no stone unturned. This guide covers natural Japanese expressions for thorough investigation, from formal inquiries to casual checking.
To conduct a detailed, often official, inquiry into a matter, such as by police, a committee, or an organization.
A standard phrase meaning 'to investigate thoroughly'. Suitable for formal contexts.
警察は事件を徹底的に調査した。
The police investigated the case thoroughly.
Means 'to examine in detail'. Less formal than 徹底的に調査する, but still appropriate for many situations.
原因を詳しく調べる必要がある。
We need to investigate the cause in detail.
Specifically used for criminal investigations. 捜査 implies a search for evidence or suspects.
当局は汚職を徹底的に捜査している。
The authorities are thoroughly investigating the corruption.
To study a topic or phenomenon exhaustively, often in a scholarly context.
Means 'to research thoroughly'. Used for academic or scientific inquiry.
その現象を徹底的に研究した。
They thoroughly researched the phenomenon.
Implies a meticulous, detailed investigation. Often used in formal reports.
市場を綿密に調査した。
We conducted a thorough investigation of the market.
To look into something carefully on your own, such as a problem, a piece of information, or a suspicious situation.
A simple, common way to say 'check carefully' or 'look into it well'. Suitable for everyday use.
その情報が正しいかよく調べてください。
Please check thoroughly whether that information is correct.
Emphasizes doing a solid, reliable investigation. Slightly more emphatic than よく調べる.
その問題をしっかり調べよう。
Let's investigate that problem thoroughly.
Literally 'to check every corner'. Conveys a very thorough, exhaustive search.
部屋を隅々まで調べた。
I searched the room thoroughly (every nook and cranny).
To look into someone's history, actions, or character in detail.
Means 'to check someone's identity/background'. Often used in security or hiring contexts.
応募者の身元を徹底的に調べた。
We thoroughly investigated the applicants' backgrounds.
Similar to 身元を調べる, but can also imply investigating someone's past or origins.
彼の素性を詳しく調べた。
I investigated his background in detail.
調べる is the general verb for 'to check/investigate'. 調査する is more formal and implies a systematic inquiry. 研究する is used for academic research. For 'investigate thoroughly', you can combine any of these with adverbs like 徹底的に (thoroughly), 詳しく (in detail), or 綿密に (meticulously).
The English phrase 'investigate thoroughly' is often best expressed with an adverb + verb combination in Japanese. A direct translation like '調査を徹底する' is less natural than '徹底的に調査する'.