It sounds like a commercial: easy on the ear but bland and forgettable.

它听起来像句广告语：顺耳却平淡易忘。

《柯林斯英汉双解大词典》

His performance in the show was dull and forgettable.

他的表演很沉闷，不堪回味。

youdao

youdao

There was a time when Italian elections were frequent and forgettable.

BBC: Europe waits for Italy elections

Some mediocre and forgettable.

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He had only a guest appearance in English Vinglish and a forgettable role in Department.

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