To Knock vs Knocking Infinitives & Gerunds

When and How to Use Each Expression?

Get a sense of when and how each expression can be used through the following examples!

To knock (Infinitive)

Purpose or Intention: Use the infinitive "to knock" when you want to express a purpose, intention, desire, or potential action

Example

I want to knock on the door and see if anyone is home.

Knocking (Gerund)

Activity or Experience: Use the gerund "knocking" when you want to refer to the activity itself or the experience as a noun.

Example

Knocking is a common sound in this old house.

Where can infinitives/gerunds be placed in a sentence?

To knock (Infinitive)

• 1. Subject

  To knock is a polite way to announce your presence.

  To knock is a polite way to announce your presence.

  • "*To knock*" serves as the subject of the sentence.
  • Infinitive phrase (subject) + verb (is) + noun phrase (a polite way to announce your presence).
• 2. Object

  She wants me to knock on her neighbor's door.

  She wants me to knock on her neighbor's door.

  • "Me *to knock* on her neighbor's door" is the object of the verb "wants."
  • Noun (She) + verb (wants) + noun phrase (me *to knock* on her neighbor's door).
• 3. Adjective Modifier

  I need a hammer to knock the nail in.

  I need a hammer to knock the nail in.

  • "*To knock* the nail in" modifies the noun "hammer."
  • Noun (I) + verb (need) + noun phrase (a hammer *to knock* the nail in).

Knocking (Gerund)

• 1. Subject

  Knocking can be heard coming from the other side of the wall.

  Knocking can be heard coming from the other side of the wall.

  • "*Knocking*" is the subject of the sentence.
  • Gerund (subject) + verb (can be heard) + noun phrase (coming from the other side of the wall).
• 2. Object

  I enjoy knocking on doors and surprising people.

  I enjoy knocking on doors and surprising people.

  • "*Knocking* on doors and surprising people" is the object of the verb "enjoy."
  • Noun (I) + verb (enjoy) + gerund (*knocking* on doors and surprising people).
• 3. Object of Preposition

  He has a fear of knocking at strangers' houses.

  He has a fear of knocking at strangers' houses.

  • "Of *knocking* at strangers' houses" is the object of the preposition "of."
  • Noun phrase (He) + verb (has) + noun phrase (a fear of *knocking* at strangers' houses).

Verbs Taking Infinitives/Gerunds as Objects

The following are verbs that can take only the base form of the verb (infinitive), only the -ing form (gerund), or both.

Verbs Taking Infinitives as Objects

• decide
• attempt
• refuse
• manage
• hope

Example

We decided to knock on their door and ask for directions.

He attempted to knock quietly so as not to wake anyone up.

They refused to knock on the door because they were afraid.

She managed to knock on all the doors in the neighborhood.

I hope to knock on the right door and find the person I'm looking for.

Verbs Taking Gerunds as Objects

• avoid
• consider
• recommend
• mind
• imagine

Example

They avoid knocking on doors late at night.

She is considering knocking on the neighbor's door to borrow some sugar.

I recommend knocking softly to avoid disturbing anyone.

Do you mind knocking on the door for me? I forgot my keys.

Can you imagine knocking on a door and finding a hidden treasure?

Verbs Taking Both Infinitives and Gerunds as Objects

• like
• begin
• continue

Example

He likes to knock on the table to get everyone's attention. He likes knocking on the table to get everyone's attention.

We began to knock on the doors of every house in the neighborhood. We began knocking on the doors of every house in the neighborhood.

They continue to knock until someone opens the door. They continue knocking until someone opens the door.