Clauses: Main and subordinate clauses

Typically, a clause expresses a particular situation – an event or state of affairs. To do this, it usually needs to contain a verb. Here is an example of a clause:

• My brother phoned my cousin on Tuesday night.

This expresses an event, with the verb phoned indicating the type of event.

Here are some more examples of clauses, with the verb phrases highlighted:

• She laughed. _{[W2F-018 #189]}
• Glass is very expensive. _{[S2B-022 #105]}
• Liverpool were rumbled in the Rumbelows Cup last night, to Old Trafford's immense satisfaction. _{[W2C-004 #20]}

The examples show that a clause can be short or long. Some special clauses contain just a verb (e.g. Stop!), but often there are additional phrases which tell us more about the situation, such as:

• who or what is involved (My brother phoned my cousin on Tuesday night)
• the circumstances, such as time or place (My brother phoned me on Tuesday night)

In our example, we have two noun phrases telling us who was involved in the phoning event (my brother and my cousin), and a preposition phrase (on Tuesday night) telling us when it took place.

When we look at the type of phrase (noun phrase, adjective phrase, preposition phrase and so on), we are looking at grammatical form. We can also look at the grammatical function of these phrases within the clause. Our example was My brother phoned my cousin on Tuesday night. Here, for instance:

• my brother occurs right before the verb and functions as Subject (it was my brother who did the phoning).
• my cousin occurs after the verb and functions as Direct Object (my cousin was the one who was phoned).

We will leave the functions aside for now (they are discussed in other resources).

A single clause on its own can also be a sentence, as with the examples we’ve looked at so far. Here are some more examples:

• Well, I've watched it fairly recently. _{[S1A-016 #48]}
• My mother lives not far from Lyme Regis. _{[W1B-014 #40]}
• This evening French police were out in force at key points around the city. _{[S2B-010 #127]}

These are called main clauses because each can stand alone as a sentence.

What about the following examples? They all have a verb but they seem incomplete in some way:

• ... which isn’t on the knobs and sliders ... _{[W2B-031 #58]}
• ... that the instrument worked well up to five megaHertz _{[S2A-041 #43]}
• If I get bored with the other company ... _{[S1A-040 #448]}
• ... to photograph it for some baby magazines _{[S1A-039 #88]}

These clauses don’t function as sentences on their own. They are called subordinate clauses because they function as part of larger clauses to make sentences.

Here are the full sentences for those examples, with the subordinate clauses marked inside them. Each whole sentence is a larger clause (a main clause), which contains a subordinate clause as part of it.

• However, there is one aspect of sound programming [which isn't on the knobs and sliders]. _{[W2B-031 #58]}
• This graph shows [that the instrument worked well up to five megaHertz]. _{[S2A-041 #43]}
• [If I get bored with the other company] I'll go to Pam's at five. _{[S1A-040 #448]}
• They wanted [to photograph it for some baby magazines]. _{[S1A-039 #88]}

Sentences can be usefully classified by the way they are made up of clauses.

We have already seen examples of a simple sentence. This consists of a main clause functioning as a sentence in its own right, with no subordinate clauses inside it:

• The maggots go in the doughnuts. _{[S1B-079 #313]}
• I got the Pearl Jam album today. _{[S1A-099 #261]}

We’ve also seen examples where a sentence consists of a main clause containing a subordinate clause. This is called a complex sentence:

• [If it is comfortable for humans], then it will be OK for computers. _{[W2B-033 #12]}
• Such moisture can cause havoc [while it persists inside a computer]. _{[W2B-033 #21]}
• [Unless he withdraws from Kuwait], the allies have no choice but to drive him out. _{[W2E-007 #58]}
• I thought [that Mostovoi was brought down inside the penalty area]. _{[S2A-014 #253]}

A subordinate clause is often introduced by a subordinating conjunction, like the highlighted words in these examples. It helps to relate the subordinate clause to the rest of the sentence.

Another type of sentence is called a compound sentence. Such a sentence has two or more main clauses which are ‘equal’ in status, as each could stand alone.

• “[She was anxious to be married], and [he was her only suitor].” _{[W2F-011 #48]}
• [You either study pure dance] or [you study dance therapy] and [there seems to be no connection between the two]. _{[S1A-001 #105]}
• [I can’t remember any specific names] but [they’re usually very good in France]. _{[S1A-009 #42]}

The clauses here are joined by coordinating conjunctions: words such as and, or and but which occur between the clauses.

There does not have to be a conjunction between all the clauses:

• [Then the ice reflects away solar heat], [the polar region cools still more], and [the icecap soon reforms]. _{[W2B-025 #66]}
• [Police become cynical], [standards fall], [they turn inwards] and [loyalties become distorted]. _{[S2B-031 #11]}

Please note that the National Curriculum prefers to refer to sentences that contain one or more clauses as multi-clause sentences.