at that time有“当时”、“那时”的意思，是一般过去时和过去进行时的标志。一般过去时表示过去某个时间里发生的动作或状态；过去进行时表示过去在某一时间段或某一段时间内正在发生或进行的动作或状态。
1.At that time we were students.
那会儿我们还是学生。
2.A train would pass through there every few minutes at that time of day.
每天那个时候每隔几分钟就会有火车经过那里。
3.What was he doing in Hyde Park at that time of the morning?
那么一大早他在海德公园干什么?
4.I cannot describe the feeling of contentment that was with me at that time.
我无法描述当时我满足的感觉。
5.Food was in short supply at that time.
食品一时接应不上。
6.The minister was in high favour at Court at that time.
那位大臣当时在宫廷里很吃香。
