想请教你，这里为什么用would be calling将来进行时态？

Question

I had been making preparations for more than two
days for a large dinner party to be held that night and knew that several of
the people I was expecting to come would be calling to cancel if the snow
continued much longer.

Answer 1

过去将来进行时表示就过去某一时间而言，将来某一时刻或某一段时间正在进行的动作。过去将来进行时也可以表示在过去某一时间之后即将进行的动作。主要用于宾语从句 中，本句就是如此。knew是并列谓语，后面是宾语从句several of
the people是宾从中的主语，would be calling是宾从中的谓语。

即I knew that several of the people would be calling to cancel
再如

They said they would be coming.
他们说了他们将要来。 (用于间接引语中）
He asked me what I should be doing six o'clock tomorrow.
他问我次日六点将正在做什么。 (用于间接引语中）
The new job he would be taking was raising racing horses.
他将要接受的新工作是养赛马。 （用于定语从句中）
He said that he could not come because he would be having a meeting.

他说他不能来因为要开会。

John told us that Mary would be coming next day.

约翰告诉我们玛丽第二天来。
I never realized that some day I would be living in China.
我从未想到将来有一天会在中国居住。
She said she would be setting off on the 10 o’clock train.
她说她将乘10点钟的火车走。来自：求助得到的回答