There must be one set of laws for the whole of the country.

必须有一套适用于全国的法律。

《柯林斯英汉双解大词典》

DIANA: There must be one thing they forgot to hide.

戴安娜：肯定有他们忘了藏的东西。

youdao

Or travel, or reading, body and soul, there must be one on the road.

要么旅行，要么读书，身体和灵魂，必须有一个在路上。

youdao

The judge promised there would be one. But,he says,for that to happen, Karadzic must first appear in court.

VOA: standard.2009.10.26

The promise of America is one immigration policy for all who seek to enter our shores, whether they come from Mexico, Haiti or Canada, there must be one set of rules for everybody.

CNN: Sharpton?answers Bush in speech

For example, there must be at least one adult on a trip for 10 to 15 children in years 4 to 6 (ages eight to 11) and at least one adult for every 15 to 20 children from year 7 (the first year of secondary school).

BBC: NEWS | UK | Education | School trips in the spotlight

There must be boundaries beyond which one does not step.

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