海鲜羹的做法大全:“at one time”和“at a time”怎样区别

来源:百度文库 编辑:高考问答 时间:2024/05/04 18:53:43

A.at a time 依次,逐一,每次.如;1.Don't try to do everything at once,take it a bit at a time.不要什么事情都一块干,要一次做一点.2.Take the pills two at a time.每次服2粒.
B.at one time一度,从前.如:At one time I used to go skiing every winter.我有一度每到冬天就去滑雪.

at a time 表示一次,每次,相当于each;
at one time 用于过去时

at one time表示曾经的意思
eg:I have heard of him at one time.

at a time表示在每一次
eg:Take the medicine 3 pieces at a time.

at one time
adv.
同时, 曾经

at a time
adv.
每次, 在某时