Cách sử dụng
The word 'deficiency' is used to describe a lack of something that is needed or should be present. It can be used in different contexts, such as a deficiency in a nutrient or vitamin, a deficiency in skills or knowledge, or a deficiency in a product or service. For example, if someone is lacking in vitamin D, they might have a deficiency. Similarly, if a student is struggling in a particular subject, they may have a deficiency in that area of knowledge. In general, deficiency is used to indicate a shortage or absence of something that is necessary or expected.