I felt nervous because I was soon to leave home for the first time.

　　　　I was to play Juliet.

　　　　The expedition was to start in a weeks time.

　　　　was/ were to have done，表示 本打算、本计划或本应当 做的事而没有做成或没有发生。如：

　　　　I was to have seen him last Wednesday，but he didnt come.

　　　　We were to have been married last year.

　　　　2. 表示 义务、应该 .（意思接近于should，must，ought to，have to） 如：

　　　　No one is to leave the building. 谁也不得离开这楼房。

　　　　You are not to smoke in this room.=You are not supposed to smoke in this room.

　　　　You are to be back by 10 oclock. 你必须十点以前回来。

　　　　3. 表示可能性，相当于can，may 如：

　　　　Such books are to be found in the library. 这样的书在图书馆里就能找到。

　　　　Not a single sound was to be heard. 一点儿声音也听不到。

　　　　Not a soul was to be seen. 看不到一个人影。

　　　　She was nowhere to be found. 哪儿也找不到她。

　　　　She was never to see his wife and family again.

　　　　5. 表示 命运，将来必然要发生的事，译作 注定。如：

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