1
redouble sth
redouble 是及物动词，后接名词，表示使某事物加倍或增强。
The government redoubled its investment in green energy.
政府加大了对绿色能源的投资。
加倍；加强；增强
先理解核心含义，再看它在真实句子里的用法。
加倍；加强；增强
to make or become twice as great, intense, or strong; to increase or intensify
The government redoubled its investment in green energy.
政府加大了对绿色能源的投资。
加倍,尤指再次加倍；大幅增加；倍增；加强。
To double, especially to double again; to increase considerably; to multiply; to intensify.
再加倍(桥牌)
To double an opponent's doubling bid.
变成两倍大。
To become twice as big.
重新加倍
To double again what was reduced to a single state.
redouble
Base
原形
redoubles
3rd person
第三人称单数
redoubling
-ing
现在分词
redoubled
Past
过去式
redoubled
Past participle
过去分词
She redoubles her efforts whenever she faces a challenge.
每当面临挑战时，她都会加倍努力。
The company redoubled its investment after the initial success.
初次成功后，公司加倍投入。
They have redoubled their commitment to the project.
他们已加倍投入该项目。
redouble 表示“加倍、增强”，常与 effort、commitment 等名词搭配；为规则动词。
Faced with the setback, the team decided to redouble their efforts to meet the deadline.
面对挫折，团队决定加倍努力以赶上截止日期。
The company redoubled its investment in research after the product failed.
产品失败后，公司加大了对研究的投资。
She is redoubling her training to prepare for the marathon.
她正在加倍训练以备战马拉松。
redouble 是及物动词，后接名词，表示使某事物加倍或增强。
The government redoubled its investment in green energy.
政府加大了对绿色能源的投资。
redouble one's efforts 是常见搭配，后接 to do 表示加倍努力去做某事。
We must redouble our efforts to meet the deadline.
我们必须加倍努力，在截止日期前完成任务。
redouble 也可作不及物动词，主语常为声音、力量等，表示变得更强烈。
The shouting from the crowd redoubled.
人群的喊叫声更响了。
Not this
We need a redouble of our efforts.
Use this
We need to redouble our efforts.
redouble 是动词，不是名词，不能用 a redouble of；这里要用动词不定式来表达‘加倍、加强’。
Not this
He redoubled to pass the exam.
Use this
He redoubled his efforts to pass the exam.
redouble 作‘加倍、加强’讲时是及物动词，后需接宾语（如 his efforts），不能直接接不定式表示目的。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
加倍努力
The school redoubled its efforts to improve student attendance.
学校加倍努力提高学生的出勤率。
提高警惕
After the threat, residents redoubled their vigilance.
收到威胁后，居民们提高了警惕。
加强承诺
The company redoubled its commitment to sustainable practices.
公司加强了对可持续经营的承诺。
增强决心
The defeat only redoubled the player's resolve to train harder.
这次失败反而增强了这名球员更加刻苦训练的决心。
加倍关注
We must redouble attention to the needs of rural schools.
我们必须加倍关注农村学校的需要。
加倍努力
In response to the challenge, the team redoubled its efforts.
面对挑战，团队加倍努力。
更加坚定决心
She redoubled her resolve to finish the marathon.
她更加坚定了完成马拉松的决心。
加倍关注
Parents should redouble their attention to online safety.
家长应该加倍关注网络安全。
Use redouble naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
把 redouble 拆成 re-（再）+ double（双倍）：使力量再翻一倍，即加倍、增强。
语域：formal 常见场景：正式书面语、新闻报道、演讲或公文 redouble 比较正式，多用于书面语或正式场合，表示“加倍、加强（努力、决心等）”，日常口语中较少用。
真正押韵的词：double、trouble、bubble、rubble——它们的重读音节均为 /dʌbəl/，与 redouble（riˈdʌbl）的第二音节相同。注意形似但不押韵的词：table（/ˈteɪbəl/）和 noble（/ˈnoʊbəl/），它们在 -ble 前的元音不同。
Dictionary facts from ECDICT, WIKTIONARY.