Nonfinite Clauses

Definition

A nonfinite clause is a group of words organized around a verb that doesn’t have tense and doesn’t agree with a subject. In practice, this means nonfinite clauses contain either -ing verbs or to infinitives. A nonfinite clause is always dependent: that means, it will be connected to a main clause to form a complete sentence in careful writing.

We say that a verb is finite when it is bounded, or limited to its subject (she works; they have finished; the teacher is talking). By contrast, a nonfinite verb won’t have an explicit subject, although you can infer the agent of the verb (the participant responsible for the state or action). For example:

Some robots are designed to work in factories. To work has no explicit subject: we don’t say “*robots to work in factories.” We know from the sentence, though, that the agent of work is still robots. In this sentence, robots is the subject of the finite verb are designed (robots is plural, so we must use are not is or be). The nonfinite clause is to work in factories.

[Learning a language] opens new opportunities. Learning has no subject and no tense. If you separate it from the rest of the sentence, it can’t stand alone (“learning a language”). The finite verb is opens: it’s present simple tense and third-person (-s). The subject of the sentence is learning a language, a nonfinite clause. Note that nonfinite clauses are grammatically singular (opens not *open). We could also say Learning languages opens new opportunities.

Researchers are focused on discovering new vaccines. Discovering has no tense. It’s not present progressive (that would be is/are discovering), and there’s no explicit subject. We know from the sentence that researchers are the agent (they discover new vaccines), but researchers is the subject of the finite verb are focused. So discovering new languages is the nonfinite clause.

To understand this process, we have to examine social factors. To understand is the nonfinite verb here: it’s in the infinitive form (to + base verb), so it has no subject or tense. We can infer from the main clause that the agent of understand must be we. The main clause is we must examine social factors: it can stand by itself. To understand this process is a nonfinite clause.

Form

Nonfinite clauses can appear in many different places in a sentence:

An important aspect of this topic, which is often taught to learners of English, is that many verbs are restricted to either -ing or to infinitive complements. For instance, we say Doctors suggest eating a varied diet but not *Doctors suggest to eat a varied diet. A small number of verbs can be followed by either form with no change in meaning. Examples include:

It’s possible to find patterns of meaning, but it’s hard to predict what complements a verb will take, so students need to learn patterns and use a learner’s dictionary. The resources below have longer lists.

Some grammar books call nonfinite -ing verbs gerunds and treat them as nouns. Sometimes, that makes sense – for example, I like apples; I like music; I like swimming. There’s not much difference between apples and music (obviously nouns) and swimming (an -ing verb, or gerund). However, it’s important to recognize that -ing verbs still behave like verbs, not nouns. For example, we can say I like eating apples. Clearly apples is the object of the verb eating (nouns can’t have objects). This also explains why we can say Buying fresh fruit is expensive but not Buying is expensive: buy is a transitive verb and needs an object (fresh fruit).

The verbs make and let are followed a bare infinitive without to. This is a common learner error. For example: The teacher let me leave the room and not *The teacher let me to leave the room. The verb help can be followed by a to infinitive or bare infinitive (can you help me [to] fix my car?).

Adjectives can also end in the -ing suffix. These are just adjectives, not nonfinite verbs. You can recognize them because they will be part of the noun group or follow a linking verb:

That’s an interesting book.

Your book is interesting.

Function

Nonfinite clauses have a number of functions. Often, they are a way of packing more information into a sentence. Compare, for example:

Researchers are interested in new vaccines.

Researchers are interested in discovering new vaccines.

Here, we have added the idea of discovery to the sentence by expanding the prepositional phrase with a nonfinite clause.

We can also use a nonfinite clause to make a process (a verb) the subject of a sentence:

Discovering new vaccines is one of the main challenges for medical researchers.

Here, the -ing clause is an alternative to a nominalization (the discovery of new vaccines), which is a little more dense and may be harder to read.

Other functions of nonfinite clauses include expressing:

purpose: cells photosynthesize to generate energy; designed to work in factories

consequence or causality: less rain falls, leading to drought

context: being a curious monkey, to understand this process

sequence or cohesion: to begin with, to conclude

clarification or explanation: meaning …

As a result, nonfinite clauses are found throughout the Explain and Inform KLUs, although they are only occasionally highlighted in the WIDA Framework.

 

Further Reading

Verbs followed by the -ing form (British Council LearnEnglish)

Verbs followed by the infinitive (British Council LearnEnglish)

Verb Patterns with -ing or infinitive (Cambridge Dictionaries)