今天我们要学的词是 deficiency. Deficiency 名词，意思是欠缺，缺陷。一项最新研究发现，People who suffer from a Vitamin D deficiency are at a higher risk for developing high blood pressure. 患维生素D缺乏症的人更容易得高血压。Each year, Vitamin A deficiencies cause 300,000 children worldwide to go blind. 维他命A缺乏症每年都会在全球造成30万个孩子失明。好的，今天我们学习的词是 deficiency, deficiency, deficiency...