来自PIE *bhel, 膨胀，鼓起。词源同ball. -d, 插入字母。

bold

bold: [OE] In Old English, bold meant simply ‘brave’; the modern connotations of immodesty or presumptuousness do not seem to have developed until the 12th century. The word goes back to a prehistoric Germanic *balthaz, based ultimately, it has been speculated, on Indo- European *bhel- ‘swell’ (the psychological link through ‘being puffed up’ via ‘adventurous courage’ to ‘audacity’ is scarcely far-fetched). If this is so it would mean bold is related to bellows, belly, billow, bolster, and possibly bellow and bell. The notion of impetuosity is perhaps retained in the related German bald ‘soon’.
=> bell, bellows, belly, billow, bolster

bold (adj.)

Old English beald (West Saxon), bald (Anglian) "bold, brave, confident, strong," from Proto-Germanic *balthaz (cognates: Old High German bald "bold, swift," in names such as Archibald, Leopold, Theobald; Gothic balþei "boldness;" Old Norse ballr "frightful, dangerous"), perhaps from PIE *bhol-to- suffixed form of *bhel- (2) "to blow, swell" (see bole).

Of flavors (coffee, etc.) from 1829. The noun meaning "those who are bold" is from c. 1300. Old French and Provençal baut "bold," Italian baldo "bold, daring, fearless" are Germanic loan-words.

1. Bold as you please, she grabbed me by the sleeve.

她真够大胆的，竟抓住了我的衣袖。

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2. He believes that students should be encouraged to experiment with bold ideas.

他认为应该鼓励学生们将大胆的观念付诸试验。

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3. The book's 85 colour lithographic plates look staggeringly fresh and bold.

这本书的85张彩色平版看起来异常鲜艳醒目。

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4. I thought his glance at me had been offensively bold.

我觉得他对我的瞥视唐突无礼。

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5. Use bold type for headings and bullet points for noteworthy achievements.

标题使用粗黑字体，显著的成就要用着重号标示。

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