⑴ 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.
⑵ 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).