soundless

adj.无声的

无声的；静谧的；安静的

形容词

1. The night was so soundless that I could hear my own heartbeat.
夜晚是如此寂静，以至于我能听到自己的心跳声。
2. The soundless footsteps of the ninja made him nearly undetectable.
忍者无声的脚步使他几乎不可察觉。