Fuerther wrote: Hi,In the sentence:'It is useful for seeing in the dark.'is the word 'seeing' a present particple or a gerund? Can you explain the difference between these two types of words, eg. when you use them?Thx, Fuerther
the complement of a preposition is always a noun (phrase).
A participle is used as an adjective, a gerund (phrase) a noun (phrase).