冴(さ)えるto be clear (of a sight, sound, colour, etc.), to be bright, to be vivid, to be crisp, to be clear-headed, to be alert, to be on the ball, to be wide awake, to look upbeat, to be perky, to be cheerful, to master (a skill), to excel at, to cleanly execute, to be satisfying, to become frigid, to become intensely cold

田舎(いなか)の夜空(よぞら)では星(ほし)が冴(さ)えています。

In the countryside night sky, the stars are shining brightly. {to be clear (of a sight, sound, colour, etc.), to be bright, to be vivid, to be crisp, to be clear-headed, to be alert, to be on the ball, to be wide awake, to look upbeat, to be perky, to be cheerful, to master (a skill), to excel at, to cleanly execute, to be satisfying, to become frigid, to become intensely cold}

プロのバイオリンの音色(ねいろ)は冴(さ)えている。

The tone of a professional violin is vivid. {to be clear (of a sight, sound, colour, etc.), to be bright, to be vivid, to be crisp, to be clear-headed, to be alert, to be on the ball, to be wide awake, to look upbeat, to be perky, to be cheerful, to master (a skill), to excel at, to cleanly execute, to be satisfying, to become frigid, to become intensely cold}

冬(ふゆ)の夜(よる)は冴(さ)えるので、温(あたた)かくして寝(ね)て下(くだ)さい。

The winter nights are frigid, so please keep warm and sleep. {to be clear (of a sight, sound, colour, etc.), to be bright, to be vivid, to be crisp, to be clear-headed, to be alert, to be on the ball, to be wide awake, to look upbeat, to be perky, to be cheerful, to master (a skill), to excel at, to cleanly execute, to be satisfying, to become frigid, to become intensely cold}

私(わたし)は冴(さ)えた赤色(あかいろ)の薔薇(ばら)に加(くわ)えて、淡(あわ)い赤色(あかいろ)の薔薇(ばら)も大好(だいす)きです。

In addition to the vibrant red roses, I also love light red roses. {to be clear (of a sight, sound, colour, etc.), to be bright, to be vivid, to be crisp, to be clear-headed, to be alert, to be on the ball, to be wide awake, to look upbeat, to be perky, to be cheerful, to master (a skill), to excel at, to cleanly execute, to be satisfying, to become frigid, to become intensely cold}

精神(せいしん)科(か)医(い)：「気分(きぶん)が冴(さ)えない時(とき)はランニングか何(なに)かで体(からだ)を動(うご)かすといいですよ。」

Psychiatrist: 'When you're feeling unable to be perky, it's good to get moving, like going for a run or something.' {to be clear (of a sight, sound, colour, etc.), to be bright, to be vivid, to be crisp, to be clear-headed, to be alert, to be on the ball, to be wide awake, to look upbeat, to be perky, to be cheerful, to master (a skill), to excel at, to cleanly execute, to be satisfying, to become frigid, to become intensely cold}