Such a person is sometimes called "an empty vessel."

这样的人有时被称作“空瓶子”。

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Shakespeare: the empty vessel makes the greatest sound.

莎士比亚：虚空之器，发声最响。

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The saying is true, "The empty vessel jakes the greatest sound. " (

“满壶不响，半壶叮当”的说法是正确的。

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They paint Mr Cameron as an unreconstructed Thatcherite, a changed man leading an unchanged party and an empty vessel all at the same time.

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Like everyone else in the story besides Stahl, the woman (played by Maria Bello) is an empty vessel, just an available reason for there to be voiceovers.

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Behind the vessel, a speedboat, a series of empty plastic oil jugs blue, green, yellow, black bobbed in the water.

NEWYORKER: Neptune��s Navy