-ing Form

We make the -ing  form by adding -ing  to the base verb and adjusting the spelling as necessary:

• work → working
• sit → sitting
• smoke → smoking

We use the -ing  form in various ways as shown below.

-ing Form for Continuous Tenses

The -ing  form is used in past, present and future continuous tenses, for example:

• Anthony was fishing.
• The boys have been playing tennis.
• We will be working  when you arrive.

-ing Form as Subject, Object or Complement

We can use the -in g form as the subject, object or complement of a clause, for example:

• Smoking  costs a lot of money.
• I don't like writing.
• My favourite occupation is reading.

Sometimes the -ing  form can also have an object itself. In this case, the whole expression [-ing  + object] can be the subject, object or complement of a clause or sentence.

• [Smoking cigarettes ] costs a lot of money.
• I don't like [writing letters ] and I hate [reading emails].
• My favourite occupation is [reading  detective stories].

-ing  Form with Adjectives and Determiners

• pointless questioning
• a settling  of debts
• the making  of this film
• his drinking  of alcohol

Note that when we use the -ing  form with an adjective   or  determiner , it does not usually take a direct object. Compare these sentences:

• Making  this film was expensive.
• The making of this film was expensive.
  not  The making this film

-ing  Form after Preposition

If we want to use a verb after a preposition, it must be in -ing  form. It is impossible to use an infinitive after a preposition. So, for example, we say:

• I will call you after arriving  at the office.
  not  I will call after to arrive at the office.
• Please have a drink before leaving.
• I am looking forward to meeting you.
• Do you object to working late?
• Tara always dreams about going  on holiday.

-ing Form after Certain Verbs

We sometimes use one verb after another verb. Often the second verb is in the to-infinitive  form, for example:

• I want  to eat.

But sometimes the second verb must be in -ing  form, for example:

• I dislike eating.

This depends on the first verb. Here is a list of verbs that are usually followed by a verb in -ing form:

• admit, appreciate, avoid, carry on, consider, defer, delay, deny, detest, dislike, endure, enjoy, escape, excuse, face, feel like, finish, forgive, give up, can't help, imagine, involve, leave off, mention, mind, miss, postpone, practise, put off, report, resent, risk, can't stand, suggest, understand

Look at these examples:

• She will consider having  a holiday.
  not  She will consider to have a holiday.
• Do you feel like going out?
• I  can't help falling  in love with you.
• I  can't stand not seeing you.

-ing Form in Passive Sense

We often use the -ing  form after the verbs need, require and want.

In this case, the -ing  form has a passive sense.

Look at these example sentences. Notice that this construction can be in any tense:

• I have three shirts that need washing . (need to be washed)
• I sent it back to the shop because it needed fixing . (needed to be fixed)
• This letter requires signing . (needs to be signed)
• The contract will require signing  tomorrow. (will need to be signed)
• The house wants repainting . (needs to be repainted)
• Your hair's wanted cutting  for weeks. (has needed to be cut)

sources : Original Link