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alarm clock
waking up; keeping oneself awake
early-morning treat (traditionally given to children in some parts of Japan); wake-up sweet
目覚ましが鳴ったのに起きられなかったよ。
The alarm rang but I couldn't wake up.
明日は早いので目覚しを六時にセットしよう。
I have to get up early tomorrow, so let's set the alarm for six.
目覚ましの音がうるさくて隣の人に迷惑かも。
The alarm sound is so loud it might bother my neighbor.