drowsiness

基本解释

Since some medicines cause drowsiness, it's best not to drive while taking them.
因为有些药会使人产生睡意，所以吃了药最好不要开车。
Only once, however, was she overcome by actual drowsiness. In that moment of oblivion her head sank gently against him.
但是也只有一次，她才真正让沉重的睡意征服了，在她昏睡的那一刻里，她轻轻地把头靠在了他的身上。
The servants thought me gone to shake off the drowsiness of my protracted watch; in reality, my chief motive was seeing Mr Heathcliff.
仆人们以为我是去摆脱我那因长久守夜而产生的困倦；其实，我主要的动机是想见到希刺克厉夫。

More severe seizures are often followed by what doctors call a "post-ictal period" of confusion and drowsiness.
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The drugs affect a neurotransmitter in the brain called acetylcholine and can cause dizziness, drowsiness, confusion, and memory loss.
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It's even possible that, like Claritin, it wouldn't cause drowsiness--although extensive study would be necessary to find that out.
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疲劳驾驶
Statistics show that most of traffic accidents caused by drivers’drowsiness, inattentiveness.
统计表明,许多的交通事故是由于司机疏忽或疲劳驾驶引起的。
心理学
困倦