one与a(an)都含“一”的意义,但在很多情况下,它们并不可以通用。本文拟归纳一下它们之间的区别。1.one强调数量;a/an强调类别:One classroom is no good.一个教室是不行的(需要更多的教室)。A classroom is no good.一个教室是不行的(需要更大的地方)。I’m going to ask him one question.我要问他一个问题(不是两个)。I’m going to ask him a question.我要问他一个问题(不是做其它事)。2.与时间名词连用作状语时,one前面的介词at,in,on等常省略;a/an除表示“每一”的意义外(见4),前面的介词一般 One and a (a) both contain the meaning of “a”, but in many cases they are not universally applicable. This article intends to summarize the differences between them. 1.one emphasizes quantity; a / an emphasis category: One classroom is no good. One classroom does not work (requires more classrooms). A classroom is no good. A classroom does not work (needs more space). I’m going to ask him one question. I want to ask him a question (not two). I’m going to ask him a question. I want to ask him a question (not to do other things). 2. When used in conjunction with a time noun as adverb, the prepositions at, in, on, etc., one before are abbreviated; a / an except for the meaning of “each” (see 4)