pass unnoticed

基本解释

Although it is relatively harmless and may pass unnoticed, it can sometimes produce an abundance of unpleasant fishy smelling discharge.
雖然它是相對無害的，竝且可能會在不知不覺，它有時會産生一種不愉快的腥味分泌物豐富。
peter69panda.blog.163.com
Usually, the rotating country “presidents” of these informal global groupings pass unnoticed: who knows, for instance, that France is taking over the G20 from South Korea?
這類非正式的世界性組織的輪值國的輪換通常不會引起注意：比如，有誰知道法國是從韓國那裡接過G20的呢？
If he had thought his behaviour would pass unnoticed, he now knows differently.
如果他之前他知道自己的問題但認爲無傷大雅，談話過後他也會有所收歛。
www.fatapple.com.cn

Unnoticed by anyone, a honeymoon couple from Hong Kong happened to pass by.
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