点击下方单词,选择对的这个单词
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及物动词
不及物动词
名词
1. 发出连续而低沉的声音;发嗡嗡声If something hums, it makes a low continuous noise.
2. 哼（曲子）When you hum a tune, you sing it with your lips closed.
1. a humming noise
e.g. the hum of distant traffic
Synonym: humming
2. the state of being or appearing to be actively engaged in an activity
e.g. they manifested all the busyness of a pack of beaversthere is a constant hum of military preparation
Synonym: busyness
多通过句子记忆单词，而不是单独死记硬背。
