A. 翻译：当我到了电影院时，电影已经开始了。
(By) (the) (time) I got to the cinema,the movie (had) (started).
后面必须用 过去完成时，才能体现比我到达的时间更早，（主句谓语用了过去式 got).
B. 求翻译：当我到达电影院的时候,电影已经结束了
When I arrived at the cinema, the film had already been over.
C. 当我们到达电影院时，电影已开始二十分钟了（翻译成英语）
翻译如下：
当我们到达电影院时，电影已开始二十分钟了
When we arrived at the cinema, the film had already been on for twenty minutes
D. 当我们到达电影院时，电影已经开始二十分钟了怎么翻译啊
When we got to the movie theatre ,the film had been on for 20 mins.
E. “当我到达电影院时，电影演5分钟了，”用英语怎么表达，（用过去完成时）
When I arrived at the cinema, the movie had already begun for 5 minutes.
F. 当我们到达电影院时，电影已经放映十分钟了怎么翻译
你好：
当我们到达电影院时，电影已经放映十分钟了
翻译为：
When we arrived at the cinema, the film has been screened ten minutes
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