What are participles and how are they used?

Participles are defined as verbal adjectives: they are formed from verbs, describing an action but are used as adjectives. For example, 'I ran away from the collapsing house' uses the participle 'collapsing'. 

Since they are used as adjectives, in Greek they agree with a noun/pronoun. While in English word order indicates agreement, in Greek this is shown through number, gender and case of both the participle and its corresponding noun/pronoun. 

Different tenses of participle have different meaning also. 

1) The present participle is used to describe an action that is simultaneous to the main verb. 

ταῦτα ἔπρατε στρατηγῶν - He did this while he was general. 

2) The future participle refers to a future time. If is often used to express purpose, often when used alongside ὡς. 

συλλαμβάνει Κῦπρον ὡς ἀποκτενῶν - He arrests Cyrus in order to put him to death. 

After a verb of motion, ὡς is often omitted. 

3) The aorist participle usually communicates an action which has occurred before the action of the main verb. 

δειπνήσας ἐχώρει - After dining, he went off. 

4) The perfect participle indicates a present state which came about as a result of a past event. 

οἱ τεθνηκότες  - The dead (lit. those who have died).