1. the subject of a sentence when an action is considered in a general sense. As a rule the Gerund as subject stands in front position except for sentences opening with introductory it (Br.E.) or there(Am.E.).
Talking mends no holes.
Learning rules without examples is difficult.
It’s foolish arguing over trifles.
There is no use talking like that to me.
2. the predicative.As predicative the gerund expresses either characterization or identity.
What he likes best in the world is travelling.
Deliberating is not delaying.
All I want is getting out of here.
Seeing is believing.
3. a) part of a compound verbal modal predicatewith verbs and verbal phrases expressing modality:
6.an adverbial modifier of time, manner, attendant circumstances, condition, purposeandcause.In this function it is preceded by the prepositions: after, before, on (upon), since, by, in, without, at, for, through, instead of, in spite of, despite.
One day, on returning to his hotel, he found a note in his room.
You will achieve a lot by telling the truth.
They danced without speaking.
But for meeting Tom, I wouldn’t have become an English teacher.