I heard by July you’d have been teaching here for ten years. 我听说到七月份，你就在这里教了10年书了。
过去完成进行时由“would have been+现在分词”构成。如：
He said that by the end of the spring term he would have been studying English for three years. 他说到了春季学期末，他就学了三年英语了。
I knew by that time he would have been working there for 30 years. 我知道到那时他他就在那儿工作满30年了。
She told me she’d have been teaching in that university for 20 years by that summer. 她告诉我到年年夏天她在那所大学教书就满20年了。
She will have been teaching in this university for 20 years by this summer.
→She told me she’d have been teaching in that university for 20 years by that summer.
I know by this time next week you’ll have been working here for 30 years.
→I knew by that time he would have been working there for 30 years.
At the time of the accident I was sitting in the back of the car，because Tom’s little boy was sitting beside him in front. If Tom’s boy had not been there I would have been sitting in front. 事故发生的时候，我坐在车子的后座，因为汤姆的小儿子坐在前边他的身旁。要是汤姆的孩子没坐在那里的话，我就会坐在前面了。
“What interesting job have you found?” Helen asked him; he knew she would have been thinking about it. “你找到什么有趣的工作啦?”海伦向他问道。他知道海伦一定会一直想这件事的。
“would have been+现在分词”结构除用于表示过去将来完成进行时外，有时其中的 would 也可能是情态动词，具有情态意义，比较表示推测或猜想等。如：
◇Latterly, they would have been reading Virgin books, watching Virgin videos and Virgin films.
◇Maybe we, it may well be that you were with other people, I wonder what sort of things if you were in a condition of speaking, what sort of things you would have been saying to them.
◇New York was swathed in sunlight and the heat would have been stifling had it not been for a gentle easterly breeze blowing in from the Atlantic.