Nothing to worry about. Sound test!

没什么，不用担心，是测试音响！

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According to the research, a sound test system is designed and provided to the succedent work.

同时根据本文的研究内容设计出合理的实验测试诊断系统，为后续工作做好准备。

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Kids can test drive the latest games on large-screen TVs with state-of-the-art sound.

孩子们可以在有高级音响效果的大屏幕电视上试玩新游戏。

《柯林斯英汉双解大词典》

(Sound) He says he thinks the missile test will not affect what he calls "the improving situation on the Korean peninsula."

VOA: standard.2009.10.13

You can't cram information about music, the sound of music, into your head the night before a test the way you might be able to in an English course or a history course.

你不可能像对待英语课,或者历史课考试那样在考试前一天晚上,将音乐中的信息或者将声音死记硬背,以便应付考试

耶鲁公开课 - 聆听音乐课程节选

That requires a sound strategic test, against a consumer-centric reality, and not just a laugh track.

FORBES: Brand Time-Out

"Although more information is needed to make a sound assessment, this test could, as North Korea has stated, demonstrate this capability, " they said in a statement.

NPR: NKorean Nuclear Test May Be Intelligence Windfall

Consumers can still expect the test to look and sound very similar to the local tests of the Emergency Alert System that are already conducted frequently in local markets on TV and radio.

FORBES: Will Right-Wing Radio Skip The National Emergency Test?