Hair's natural shine is supplied by its own conditioner, sebum, an oil composed of waxes and fats and also containing a natural antiseptic that helps fight infection. Too much sebum results in greasy hair and conversely, too little sebum makes dry hair. 頭髮的自然光澤來自它自身的護髮素：油脂，它含有蠟和脂肪，還含有抗感染的自然抗菌劑。油脂含量過多會導致油性發質，相反，油脂含量過少則會導致乾性發質。
The man who is a pessimist before forty-eight knows too much; the man who is an optimist after forty-eight knows too little. 未逾四十八歲的悲觀主義者，是知道得太多之人; 而年逾四十八歲的樂觀主義者，是知道得太少之人。
Too much work and too little rest often lead to illness. 過量的工作和過少的休息會引起疾病。
