We mustn't speak loudly.

我们不能大声说话。

youdao

It's impolite to speak loudly in public.

在公共场合大声说话是不礼貌的。

youdao

We should keep quiet in the cinema. We mustn't speak loudly.

我们在电影院应该保持安静。我们不能大声说话。

youdao

Every time the friends try to speak, another group of people starts singing the word SPAM very loudly.

VOA: special.2009.04.19

What I mean is that this tool doesn't speak loudly; it whispers, and you have to lean forward to hear it.

我是说那种工具声音不会很大;,它是低语的，你不得不倾身细听。

耶鲁公开课 - 现代诗歌课程节选

She once said that hands speak almost as loudly as words.

VOA: special.2009.11.15

Ask attendees to speak loudly and clearly and preface all comments or questions with their name, so everyone will know who is speaking.

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They speak loudly and warmly to each other in an accent that alternates between a drawling slang and a polite and mannered form of address.

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Speak too loudly, stand in the wrong place, and you're on the wrong side of it.

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