by the end of 后面接过去时间时，句子的时态通常用过去时态——比如过去完成时、一般过去时、过去进行时等。
用于表示时间的场合
往往含有“不迟于”的意味。
例：by the end of January
一月底之前(指一月份结束前的几天)
We are to complete the task by the end of the year.
年底之前我们必须完成此项任务。
有时 by the end of...所表示时间并不修饰谓语动词，而是修饰句中的非谓语动词，此时与句子时态无关。
如：We were working full steam ahead to finish the project by the end of April. 为了赶在四月底以前完成这个项目，我们全力以赴。（by the end of April 修饰不定式 to finish…）
用过去完成时
强调在所提及的过去时间之前已完成的动作，句子暗示两个时间：一个是 by the end of 后面的过去时间，另一个是“the end of + 过去时间”之前的时间。
如：By the end of last month, I had planted thousands of trees.
到上个月末，我已经种了数千棵树了。
By the end of last month, he had been robbed at least three times.
到上月底，他已被抢了至少三次。
I’d had a bellyful of his family by the end of the weekend.
到周末的时候，我已经受够了他一家人。
By the end of the day we had sold over 2000 tickets.
那一天下来我们卖出了两千多张票。
By the end of that year Henry had collected more than a thousand foreign stamps.
到那年年底，亨利已收集了一千多张外国邮票。
By the end of the evening she had abandoned all pretence of being interested.
到晚会结束时，她已将假装的兴趣抛得一干二净。
用一般过去时
只表示动词发生在过去，不强调在所提及的过去时间之前已经完成，此时将整个的“by the end of + 过去时间”看作一个整体的过去时间。如：
By the end of that first year, I knew how totally unsuited we were to each other.
到了第一年年底，我明白了我们俩根本不般配。
By the end of 1989 the group had assets of 3.5 billion francs.
到1989年底该集团拥有的资产达35亿法郎。
Italy became a satellite state of Germany by the end of the 1930s.
意大利在 20 世纪 30 年代末成了德国的附庸。
By the end of the year, the rebels had control over the northern territories.
到这一年的年底，叛乱分子已经控制了北方地区。
By the end of the century, France had made peace with Britain.
到那个世纪末，法国和英国议和了。
用过去进行时
表示“by the end of + 过去时间”之前正在进行或发生的情况。
如：By the end of 1942, things were starting to change.
到了 1942 年年末，情况开始有了变化。
By the end of the week, they were all getting on each other’s nerves.
p分页标题e到周末时，他们互相都很反感对方。
That man made me so angry that by the end of the meeting I was spitting blood!
那人真令我生气，到会议结束时我简直恨得咬牙切齿！
