If you are travelling alone, the single room supplement is $25 a night.

如果你独自一人旅行，单人间的额外费用是每晚$25。

《柯林斯英汉双解大词典》

The apartments are ideal for single people living alone.

这些公寓供单身者独自居住最为理想。

《牛津词典》

Because alone as single plants, they cannot survive.

因为它们无法作为单株的植物存活。

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"These are challenges that no single nation, no matter how powerful, can confront alone.

VOA: standard.2009.04.11

The atmosphere is convivial -- I didn't eat a single meal alone -- and the talk revolves around gecko sightings and how to avoid leaving.

CNN: The secret islands of Southeast Asia

This single demographic alone impacts vacation packages, resort construction, even automobiles.

FORBES: The Singularity Is Here

From a single crane bowing alone to a mated pair jumping and turning around one another, each dance has a meaning.

BBC: Nebraska��s awe-inspiring crane migration