The Differences of gerund and Present Participle

The '-ing' form of the verb may be a present participle or a gerund.

The form is identical, the difference is in the function, or the job the word does in the sentence.

The present participle:

This is most commonly used:

• as part of the continuous form of a verb,

a.      she has been waiting

b.      he is painting

c.       I am teaching

d.      They were understanding

e.       We are smiling

• after verbs of movement/position in the pattern:
  verb + present participle,

a.      she sat looking at the sea

• after verbs of perception in the pattern:
  verb + object + present participle,
  We saw him swimming

• as an adjective, e.g. amazing, worrying, exciting, boring

The gerund:

This always has the same function as a noun (although it looks like a verb), so it can be used:

• as the subject of the sentence:
  Eating people is wrong.

• after prepositions:
  Can you sneeze without opening your mouth?
  She is good at painting

• after certain verbs,
  e.g. like, hate, admit, imagine

• in compound nouns,
  e.g. a driving lesson, a swimming pool, bird-watching, train-spotting