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-ed participle

-ed participles may occur as simple (non-tensed) phrases:

Danzig (Gdansk) became a ‘free city’, 

linked by a customs union to the new

Polish state, which also gained Upper Silesia, a major industrial area. 

In complex phrases, they combine with the -ing participle and to-infinitive forms of

be

and have to create passive voice and perfect aspect, or a combination of both:

Being consulted on the matter would have been nice too. 

(passive)

To be forced to leave, be rejected by his own people, must have been a double blow.

(passive)

Having written so many letters and not got an answer, I’m not sure it’s worth

writing another one. 

(perfect)

To have worked so hard and then to have that done to them overnight! 

(perfect)

Having been fired only the day before for not doing any work, I was eager to

appear busy. 

(perfect and passive)

It was petty of me, I know, 

to have been irritated by such a fellow, but I was.

(perfect and passive)