1. 过去将来时 (Past Future Simple Tense)
1.1 结构
公式:would + 动词原形
I said I would do my homework tomorrow. (我说我明天会做家庭作业。)
1.2 用法
表示从过去某个时间来看，将来某一时间要发生的动作或事件
定义：过去将来时通常用来表示在过去某个时间点，某人说或计划在将来要做的事情。它主要用于间接引语或表示过去的打算。
例句：
She promised she would help me tomorrow.
(她答应过我，明天会帮我。)
He said he would visit his grandmother next week.
(他说他下周会去看望奶奶。)
表示过去的计划、意图或承诺
定义：过去将来时常用于描述过去的计划或意图，强调在过去某个时刻，某个动作或事件是未来要发生的。
例句：
I thought I would finish the book by last weekend.
(我以为上周末之前会读完这本书。)
1.3 标志性词语 (Signal Words)：
这些词语常和过去将来时连用，表示从过去看某一未来的计划、意图或预测：
tomorrow(明天)
next week/month/year(下周/下月/明年)
soon(很快)
the day after tomorrow(后天)
例句：
I knew I would leave by tomorrow.
(我知道我会在明天离开。)
She said she would finish the report by next Monday.
(她说她会在下周一之前完成报告。)
2. 过去将来进行时 (Past Future Continuous Tense)
2.1 结构
公式:would be + 动词的现在分词 (V-ing)
I said I would be doing my homework at 8:00 tomorrow. (我说过了我明天8点正在做作业。)
2.2 用法
表示在过去的某个时间，计划在未来某一时间点正在进行的动作
定义：过去将来进行时用于表示从过去某个时间来看，未来某个时间点正在进行的动作。这个时态强调动作的持续性。
例句：
He said he would be working at 9 AM tomorrow.
(他说他明天早上9点会在工作。)
She mentioned that she would be attending a meeting at that time.
(她提到她当时会参加会议。)
表示从过去某一时刻推测，未来某个时间的持续动作
定义：此时态表示过去某个时间对未来某个时间点的预测，特别是对持续进行中的动作的预期。
例句：
They told me they would be traveling in Europe next summer.
(他们告诉我，明年夏天他们会在欧洲旅行。)
2.3 标志性词语 (Signal Words)：
tomorrow(明天)
next week/month/year(下周/下月/明年)
at that time(那时)
soon(很快)
例句：
I knew at that time I would be studying at 8 PM tomorrow.
(我知道那个时候，明天晚上8点我会在学习。)
He said he would be flying to New York soon.
(他说他很快会飞往纽约。)
3. 过去将来完成时 (Past Future Perfect Tense)
3.1 结构
公式:would have + 过去分词 (V-ed / V-en)
I said I would have done my homework before you opened the door. (我说过在你开门之前我会做好功课。)
3.2 用法
表示从过去的时间来看，将来某一时刻已经完成的动作
定义：过去将来完成时表示在过去某个时间点，某个动作在未来某一时刻之前将会完成。
例句：
I told them I would have finished the report by tomorrow.
(我告诉他们，明天之前我会完成报告。)
She said she would have arrived by noon.
(她说她中午之前会到达。)
表示过去对未来完成的动作的预测或计划
定义：过去将来完成时常用于表示对某个未来时刻的预测或计划，即某个动作在未来某个时间点会完成。
例句：
I thought by the time you arrive, I would have already left.
(我以为等你到达时，我已经离开了。)
3.3 标志性词语 (Signal Words)：
by + 时间点(表示某个时间点之前)
before + 时间点(在某个时间点之前)
by the time(到...时)
例句：
I said I would have completed my task by 5 PM.
(我说过，5点之前我会完成我的任务。)
By the time we arrive, they would have already left.
(等我们到达时，他们应该已经离开了。)
4. 过去将来完成进行时 (Past Future Perfect Continuous Tense)
4.1 结构
公式:would have been + 动词的现在分词 (V-ing)
They said tomorrow they would have been using Xinjiang cotton for ten years. (他们说了明天将是他们使用新疆棉花的第十周年纪念。)
4.2 用法
表示过去某个时间点，预测将来某一时刻已经完成并且还在持续进行的动作
定义：过去将来完成进行时表示在过去某个时间点，某个动作在未来某个时刻之前已经完成，并且这个动作还会持续进行。
例句：
By next year, I would have been studying English for five years.
(到明年，我将已经学习英语五年了。)
He said by the time they arrive, we would have been working for three hours.
(他说，当他们到达时，我们将已经工作三个小时了。)
表示过去的某个时间点对未来某一时刻的预测，强调动作的持续性和完成性
定义：过去将来完成进行时强调某个动作将在未来某一时刻已经完成并且还会持续。
例句：
They said by next month, they would have been living in the city for 10 years.
(他们说到下个月，他们将在这个城市生活满十年。)
4.3 标志性词语 (Signal Words)：
by + 时间点
by the time(到...时)
next month(下个月)
tomorrow(明天)
例句：
By next year, I would have been working here for five years.
(到明年，我将已经在这里工作五年了。)
They said they would have been using this technology for a decade by next month.
(他们说下个月时，他们将已经使用这种技术十年了。)
