A visit to the museum is an unforgettable experience.

对该博物馆的参观是一次难忘的经历。

《柯林斯英汉双解大词典》

In the end, that Thanksgiving became an unforgettable experience.

最后，那次感恩节成为了一次难忘的经历。

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Having a go at training professional players was an unforgettable experience.

尝试训练职业球员是一次难忘的经历。

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But studying there was ultimately a fulfilling and unforgettable experience that broadened his interests and taught him to remain a perpetual student.

ECONOMIST: Face value

On Christmas day, High Mass at the Duomo is an unforgettable experience.

CNN: The story

Viewing the vast tranches of rock from the air on a helicopter ride or from the transparent Skywalk will be an unforgettable experience for any child.

BBC: Five family-friendly adventures