Translation guide
The English adverb "extensively" describes something done in a thorough, wide-ranging, or detailed manner. In Japanese, there is no single direct equivalent; the best choice depends on whether you mean "covering a wide area/range," "in great detail," or "to a large degree."
Expressing that something is done over a broad scope, involving many places, people, or topics.
The most common and versatile adverb for "widely" or "extensively." Used when an action or state covers a broad area or range.
彼の作品は広く知られている。
His works are extensively known.
この問題は広く議論された。
This issue was extensively discussed.
Emphasizes a wide range or variety, often used for activities, knowledge, or offerings.
彼女は幅広く本を読んでいる。
She reads extensively (across a wide range of books).
Formal phrase meaning "across many fields" or "in many areas." Suitable for academic or business contexts.
彼は多方面にわたって研究を行った。
He conducted research extensively across many fields.
Expressing that something is done thoroughly, with careful attention to many aspects.
The standard adverb for "in detail" or "thoroughly." Use when "extensively" means covering a topic with depth.
その点について詳しく説明してください。
Please explain that point extensively.
彼はその事件を詳しく調べた。
He investigated the incident extensively.
Means "thoroughly" or "exhaustively." Stronger than 詳しく, implying no stone left unturned.
彼らはその問題を徹底的に分析した。
They analyzed the problem extensively.
Means "minutely" or "in fine detail." Suitable when "extensively" refers to covering many small points.
彼はその計画を細かく説明した。
He explained the plan extensively (in fine detail).
Expressing that something is done a lot, heavily, or on a large scale.
Adverb meaning "greatly" or "very much." Often used when "extensively" modifies a verb like "use," "rely on," or "benefit."
彼はその技術を大いに活用した。
He made extensive use of that technology.
Casual adverb meaning "considerably" or "quite a lot." Works for informal contexts.
Means "substantially" or "drastically." Used for changes, revisions, or increases.
その法律は大幅に改正された。
The law was extensively amended.
There is no single Japanese adverb that covers all uses of "extensively." Translating it as 拡張的に (kakuchōteki ni) or 広範囲に (kōhan'i ni) in every case will sound unnatural. Choose the option that matches the intended nuance.
広く (widely) is for breadth, while 詳しく (in detail) is for depth. If you say 広く説明する, it means explaining to a wide audience; 詳しく説明する means explaining in detail.
彼女はアジアを広く旅行した。
She has traveled extensively in Asia.
その報告書は経済的影響を詳しく扱っている。
The report extensively covers the economic impact.
The book was extensively rewritten.