oxford_guide_to_english_grammar

16 PARTICIPLES
PAGE 168
2 An active participle is the ing-form of a verb, e.g. laughing, waiting.
I heard you laughing. We sat there waiting patiently.
This form is the same as a gerund. • 129(2)
3 A passive or past participle is a form such as covered, annoyed, broken, left.
Although covered by insurance, Tom was annoyed about the accident.
I stepped on some broken glass.
There were two parcels left on the doorstep.
A regular form ends in ed. For irregular forms, • 300.
4 A passive participle can be simple or continuous.
Simple: They wanted the snow cleared away.
Continuous: We saw the snow being cleared away.
5 A participle can also be perfect.
Having waited an hour, the crowd were getting impatient.
Having been delayed for an hour, the concert started at nine o'clock.
6 In the negative, not comes before the participle.
He hesitated, not knowing what to do.
Not having been informed, we were completely in the dark.
136 Participle clauses
1 A participle clause can be just a participle on its own.
Everyone just stood there talking.
There can be an object or adverbial.
We saw a policeman chasing someone.
Cut above the right eye, the boxer was unable to continue.
An adverbial usually comes after the participle, and an object always comes after it.
NOT We saw a policeman someone chasing.
NOTE For adverb + participle + noun, e.g. rapidly rising inflation, • 137(2).
2 A participle can sometimes have a subject.
The lights having gone out, we couldn't see a thing.
If there is no subject, then it is understood to be the same as in the main clause.
The men sat round the table playing cards.
(The men were playing cards.)
NOTE
The understood subject is usually the same as in the main clause.
Walking across the field, we saw a plane fly past.
(= As we were walking..., we saw...)
We cannot use a main clause without we, the understood subject of the participle.
NOT Walking across the field, a plane flew past.
This suggests that the plane was walking across the field, which is nonsense.
Now look at this example.
Sitting at a table, the band played for them.
This might lead to a misunderstanding because it suggests that the band was sitting at a table.
The following sentence is correct.
Sitting at a table, they listened to the band.
(= As they were sitting..., they listened...)