Grammar B1 Complex Noun Phrases

Postmodification with infinitive phrases

Postmodification with infinitive phrases

What is Postmodification with Infinitive Phrases?

Postmodification means adding extra information after a noun to describe or explain it. An infinitive phrase is a group of words that starts with the infinitive form of a verb (to + verb). When you use an infinitive phrase after a noun, you give more details about what the noun is, what it does, or what you can do with it. For example: "I have a book to read" — the phrase "to read" modifies the noun "book" and tells us the purpose of the book.

Why Use Infinitive Phrases?

Infinitive phrases help you write longer, more natural sentences without using extra clauses. Instead of saying "I need a person who can help me", you can say "I need a person to help me". Both mean the same thing, but the infinitive phrase is shorter and sounds more fluent. This is very common in spoken and written English, especially when you want to describe the purpose or function of something.

Common Patterns

The most common nouns that take infinitive phrases are: things with a purpose (book, tool, place), people with a role (person, teacher, doctor), and abstract nouns (ability, chance, decision). After these nouns, you can add "to + verb" to show what the noun is for or what can be done with it. The infinitive phrase always comes directly after the noun, with no other words between them in most cases.

Types of Nouns and Their Infinitive Postmodifiers

Noun Type Infinitive Pattern Example Note
Purpose nouns noun + to-infinitive a tool to measure pressure Infinitive expresses what the noun is used for
Role / function nouns noun + to-infinitive the person to contact Identifies who fulfils a particular function
Sequence / order nouns ordinal noun + to-infinitive the first student to arrive Common with first, last, next, only
Abstract quality nouns noun + to-infinitive the ability to adapt Nouns like ability, desire, tendency, need
Opportunity / chance nouns noun + to-infinitive an opportunity to speak Nouns like chance, opportunity, time, moment
Decision / plan nouns noun + to-infinitive a plan to expand the network Nouns like decision, plan, proposal, attempt
Way / method nouns noun + to-infinitive the best way to solve it Nouns like way, method, approach, means
Quantity / amount nouns noun + to-infinitive enough money to buy a ticket Often preceded by enough or too much/little
Formula
✔ Positive
Noun + + infinitive phrase + (to + verb + object)
I bought a notebook to write my ideas.

Examples

I have some homework to do before tomorrow.
I have some homework to do before tomorrow.
Purpose · The infinitive phrase shows what the homework is for
Do you have any plans to visit Paris next year?
Do you have any plans to visit Paris next year?
Intention · The infinitive phrase describes the purpose of the plans
We need a ladder to reach the top shelf.
We need a ladder to reach the top shelf.
Function · The infinitive phrase explains what the ladder is used for
She is looking for a place to live in the city.
She is looking for a place to live in the city.
Location/purpose · The infinitive phrase shows the intended use
They gave me a task to complete by Friday.
They gave me a task to complete by Friday.
Obligation · The infinitive phrase describes what must be done
He is the right person to lead this project.
He is the right person to lead this project.
Ability/suitability · The infinitive phrase shows what the person can do
When to use it
Describing Purpose
Use infinitive phrases to explain why something exists or what it is for. This is the most common use.
"I need a tool to open the paint can."
Listing Tasks
Describe what tasks or actions someone must complete or should do.
"She has three reports to write this week."
Describing People
Explain what role a person has or what they are able or supposed to do.
"We need a teacher to help students with mathematics."
Describing Places
Show the intended purpose or use of a location.
"They found a house to rent near the school."
Signal words
to do to go to buy to use to help to solve to make to find to visit to learn
Common Mistakes
Wrong
I have a book reading.
Correct
I have a book to read.
Use infinitive (to + verb), not gerund (-ing form), after nouns for purpose.
Wrong
She wants a job to make money and for travelling.
Correct
She wants a job to make money and to travel.
Keep the same structure: use 'to' + infinitive in both parts of the list.
Wrong
He has no time for to study.
Correct
He has no time to study.
Do not use 'for' before the infinitive phrase in this structure.
Wrong
I gave her money to buying a new car.
Correct
I gave her money to buy a new car.
Use base infinitive (to buy), not gerund (buying), after infinitive phrase.
KEY TAKEAWAYS

What to Remember

  • Infinitive phrases begin with "to + verb" and come after a noun to add information.
  • Use infinitive phrases to show the purpose, function, or what you can do with something.
  • The infinitive phrase modifies the noun that comes directly before it in the sentence.
  • Infinitive phrases are common after nouns like "book," "way," "time," "place," and "reason."
  • Don't confuse infinitive phrases with gerunds; infinitive phrases use "to + verb," not "-ing" forms.
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