-ing form

La forma -ing es usada:

• como sustantivo

          Smoking is very bad for your health.

• después de ciertos verbos: admit, appreciate, avoid, continue, deny, fancy, go (for activities), imagine, mind, miss, quit, save, suggest, practise, consider, prevent, etc

          Can you imagine winning the lottery?

• después de love, like, enjoy, prefer, dislike, hate, etc para expresar preferencia

          Jamie enjoy talking to his friends on the phone.

      pero para expresar una preferencia específica (would like, would prefer, 

       would love) usamos to-infinitive:

          I would love to go to New York.

• después de expresiones como be busy, it's no use, it's (no) good, it's (not) worth, what's the use of, can't help, there's no point in, can't stand, have difficulty (in), have trouble, etc

          There is no point in talking to the boss about it, he never listens to 

          us.

• después de spend, waste or lose (time, money, etc)

          He spent a lot of time and money repairing his car.

• después de la preposición to con verbos y expresiones como look forward to, be used to, in addition to, object to, prefer (doing something to something else)

          He prefers swimming to playing football.

• después de otras preposiciones

          He was thinking of quitting his job.

• después de los verbos hear, listen to, notice, see, watch y feel para describir una acción incompleta

          I heard Nicky talking to Chris. (I only heard part of the conversation)

       Usamos el infinitivo sin to con los verbos anteriores para describir la 

       acción completa

          I heard Nicky tell the story. (I heard the whole story)