a determiner (NOT PARTICULAR)
A1 used before a noun to refer to a single thing or person that has not been mentioned before, especially when you are not referring to a particular thing or person
一（個）（用於名詞前，表示未曾提及的，尤其是非特指或不想讓對方確切知道的事物或人）› used before some uncountable nouns when you want to limit their meaning in some way, such as when describing them more completely or referring to one example of them
（用於一些不可數名詞前，在某種意義上起限定性作用）A2 used before some nouns of action when referring to one example of the action
（用於某些行為名詞前）一下，一次A2 used when referring to a unit or container of something, especially something you eat or drink
（尤指飲食的）一份，一客A2 used before the first but not the second of two nouns that are referred to as one unit
（用於被視為一體的兩個名詞中的第一個詞前）一副，一套，一組A2 used before some words that express a number or amount
（用於某些表示數量的詞前）› used in front of a person's name when referring to someone who you do not know
（用於不認識的人名前）有個，某一（個）› used in front of someone's family name when they are a member of that family
（用於某人的姓之前，表示其為該姓家族成員）
