ing participle

-ing participle (presens partisipp): the (non-finite) verb form ending in -ing . The -ing participle combines with the grammatical auxiliary be to express the progressive aspect (They are singing). An -ing participle can also be the verb of a non-finite clause (Pacing round the lake, she calculated when the reply might arrive.). -ing participles can also be used as adjectives: a charming smile, the approaching train, an ageing professor.