一、"would+动词原形"表示过去将来时
"would+动词原形"构成过去将来时，常表示根据计划或安排即将发生的事。
例1：He said he would come to see me.他说他要来看我。
例2：He told me he would go to Beijing.他告诉我他将去北京。
二、"was /were+going to+动词原形"表示过去将来时
"was /were+going to+动词原形"也可表示根据计划或安排即将发生的事。
例1：She said she was going to start at once.她说她将立即出发。
例2：I was told that he was going to return home.有人告诉我他准备回家。
"was /were+going to+动词原形"还可表示根据当时情况判断有可能但不一定会发生某事。
例：It seemed as if it was going to rain.看来好像要下雨。
三、某些动词的过去进行时可表示过去将来时
come,go,leave,arrive,start等严格按照时间表发生的表起止的动词可用过去进行时代替过去将来时。
例1：He said the train was leaving at six the next morning.他说火车第二天早晨出发。
例2：She told me she was coming to see me.她告诉我她要来看我。
四、特定场合的一般过去时可表示过去将来时
条件状语从句和时间状语从句中须用一般过去时代替过去将来时。
例1：I didn't know when she would come, but when she came I would let you know.我不知道她什么时候来，但她来了我会告诉你。
析：第一个when引导宾语从句，可使用将来时，第二个when引导时间状语从句，只能用一般过去时代替过去将来时。
例2：I didn't know if she would come,but if she came I would let you know.我不知道她是否来，但如果她来我会告诉你。
析：第一个if引导宾语从句，可使用将来时，第二个if引导条件状语从句，只能用一般过去时代替过去将来时。