[译] 一个贫穷的老人曾在这所房子里住过。
[误] At a time a poor old man lived in this house.
[正] At one time a poor old man lived in this house.
[注] at one time 与 at a time 意思不同,用法也不同。at one time 意为“曾经”、“从前有段时间”,因而同过去式连用。又如:At one time most school teachers were men, but today there are more women than men.从前有一段时间大多数学校的教师都是男的,但今天的学校女教师多于男教师。
