点击下方单词,选择对的这个单词
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名词
1. （尤指不快之事的）开始，开端，肇始The onset of something is the beginning of it, used especially to refer to something unpleasant.
1. (military) an offensive against an enemy (using weapons)
e.g. the attack began at dawn
Synonym: attackonslaughtonrush
2. the beginning or early stages
e.g. the onset of pneumonia
Synonym: oncoming
多通过句子记忆单词，而不是单独死记硬背。
