用May-December romance这个短语来表示“忘年恋”大概是表示这段浪漫关系中年轻的一方处于生命的“春天”(即“五月”)，而年长的那一方则可能处于生命的“冬季” (即“十二月”)。

The phrase comes from the younger person being in the "spring" of his or her life (i.e., May)， while the older partner is in his or her "winter" (i.e., December)。

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这段时间的流行风格是柔和、浪漫。

This season's look is soft and romantic.

《牛津词典》

这段经历并不是你所想象的那么浪漫。

The experience was not as romantic as you imagine.

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