Hear, see, etc + object + verb form

I heard him go/going.

Hear, see, watch, notice and similar verbs of perception can be followed by object + infinitive (without to) or object + -ing form.

• I heard him go down the stairs. OR I heard him going down the stairs. (not I heard him went down the stairs.)

There is often a difference of meaning. After these verbs, an infinitive suggests that we hear or see the whole of an action or event; an -ing form suggests that we hear or see something in progress, going on. Compare:

• I saw her cross the road. (= I saw her cross it from one side to the other.)
  I saw her crossing the road. (= I saw her in the middle, on her way across.)
• I once heard him give a talk on Japanese politics.
  As I walked past his room I heard him talking on the phone.
• Watch me jump over the stream.
  I like to watch people walking in the street.
• I heard the bomb explode. (not I heard the bomb exploding.)
  I saw the book lying on the table. (not I saw the book lie …)

A progressive form can suggest repetition.

• I saw her throwing stones at the other children.

After can see/hear (which refer to actions and events that are in progress, (see here), only the -ing structure is used.

• I could see Jack getting on the bus. (not I could see Jack get …)

These structures can be used after passive forms of hear and see. In this case, the infinitive has to.

• He was never heard to say ‘thank you’ in his life. (not He was never heard say …)
• Justice must not only be done; it must be seen to be done.
• She was seen walking away from the accident.

Passive forms of watch and notice are not used in this way.

Possessives not used

After these verbs, possessives cannot be used with -ing forms.

• I saw Chloe talking to Mia. (not I saw Chloe’s talking to Mia.)

I heard my name repeated.

In this structure, the past participle has a passive meaning.

• I heard my name repeated several times. (= My name was repeated.)
• Have you ever seen a television thrown through a window?

The idea of ‘action or event in progress’ can be given by a progressive form (being + past participle).

• As I watched the tree being cut down …
• I woke up to hear the bedroom door being opened slowly.

Look at him eating!

Look at can be followed by object + -ing form, and in American English also by object + infinitive.

• Look at him eating!
• Look at him eat! (AmE)

note

For more about verbs that can be followed by both infinitives and -ing forms, (see here).

For the difference between hear and listen, (see here).

For see, look and watch, (see here).