I had thought to return early but they wouldn't let me go.
在谈及由hope, intend, mean以及think等词所表达的未实现的愿望时，可以用过去完成时态，这是该时态的常见用法。所为过去完成时态就是过去时与完成时的结合，它表示在过去的某个时期或时刻之前已经完成的动作或存在的状态，动作或状态的时间一直延伸到过去某个时刻。
(1) When I arrived she had just left.
(2) I heard that he made an important discovery.
(3) As soon as she had done it, she knew it was a mistake.
(4) I had intended to come over to see you, but was prevented from doing so.
语法分析：有些词如hope, plan, mean, expect, intend, suppose, want以及think等有时用过去完成时表示一个本来打算做而未做，曾经设想而未实现的事。
(5) He got here before I had got up.
(6) We would get into trouble as soon as the gas had run out.
(1) She told me that she ______[break] her glasses yesterday.
(2) The bell rang before I ______[complete] my paper.
(3) I _____[think] that he had died at least two years ago.
(4) I _____[hope] to enter a university, but didn't.
(5) The concert was more successful than she _____[think].
(6) She wore the necklace her mother _____[leave] her.
(7) When he _____[sing] his song he sat down.
(8) She told me that she _____[know] me since she was a child.
(1) had broken (2) had completed (3) has thought (4) had hoped (5) had thought (6) had left (7) had sung (8) had known