A low voice或soft-voiced
参考例句:
In a whisper;in a quiet voice低声耳语
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低声地短语:
below one's breath
beneath one's breath
between the teeth
in a pig's whisper
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同意词:
undertonesn. 低调( undertone的名词复数 ),低声地,淡色,潜在的感情
lowingn. 牛叫声; v.低声叫(low的ing形式)
whisperer低声说话的人;拨弄是非的人;告密者;〈美〉(剧中)提词人