THE GERUND

This looks exactly the same as a present participle, and for this reason it is now common to call both forms 'the -ing form'. However it is useful to understand the difference between the two. The gerund always has the same function as a noun (although it looks like a verb), so it can be used:
a. as the subject of the sentence:

• Eating people is wrong.
• Hunting tigers is dangerous.
• Flying makes me nervous.

b. as the complement of the verb 'to be':

• One of his duties is attending meetings.
• The hardest thing about learning English is understanding the gerund.
• One of life's pleasures is having breakfast in bed.

c. after prepositions. The gerund must be used when a verb comes after a preposition:

• Can you sneeze without opening your mouth?
• She is good at painting.
• They're keen on windsurfing.
• She avoided him by walking on the opposite side of the road.
• We arrived in Madrid after driving all night.
• My father decided against postponing his trip to Hungary.

This is also true of certain expressions ending in a preposition, e.g. in spite of, there's no point in..:

• There's no point in waiting.
• In spite of missing the train, we arrived on time.

d. after a number of 'phrasal verbs' which are composed of a verb + preposition/adverb
Example:
to look forward to, to give up, to be for/against, to take to, to put off, to keep on:

• I look forward to hearing from you soon. (at the end of a letter)
• When are you going to give up smoking?
• She always puts off going to the dentist.
• He kept on asking for money.

NOTE: There are some phrasal verbs and other expressions that include the word 'to' as a preposition, not as part of a to-infinitive: - to look forward to, to take to, to be accustomed to, to be used to. It is important to recognise that 'to' is a preposition in these cases, as it must be followed by a gerund:

• We are looking forward to seeing you.
• I am used to waiting for buses.
• She didn't really take to studying English.

It is possible to check whether 'to� is a preposition or part of a to-infinitive: if you can put a noun or the pronoun 'it' after it, then it is a preposition and must be followed by a gerund:

• I am accustomed to it (the cold).
• I am accustomed to being cold.

e. in compound nouns

Example:

• a driving lesson, a swimming pool, bird-watching, train-spotting

It is clear that the meaning is that of a noun, not of a continuous verb.

Example:

• the pool is not swimming, it is a pool for swimming in.

f. after the expressions:
can't help, can't stand, it's no use/good, and the adjective worth:

• She couldn't help falling in love with him.
• I can't stand being stuck in traffic jams.
• It's no use/good trying to escape.
• It might be worth phoning the station to check the time of the train.