A sentence is a group of words that makes complete sense, contains a main verb, and begins with a capital letter. Sentences are used:

  • to make statements:

I took some money out of the bank.

The shop stays open until 9 p.m.


  • to ask questions or make requests:

Can I help you?

Could you open the door?


  • to give orders:

Stop arguing!

Come here at once!


  • to express exclamations:

You’re driving too fast!

It’s so cold!

Sentence or not?

The examples in the section above all show well-formed sentences. None of the following examples are proper sentences: can you work out why?

"Ham and eggs. And onions."

Too much information!

"Not at all, Joe."

which Rob shook

if it ever became public

The first three are not sentences because they do not contain a verb: they would be acceptable in informal speaking and writing, because they are easy to understand, but you should avoid using such constructions in formal situations.

The last two are not proper sentences because they do not contain a main verb or make sense on their own (they are in fact subordinate clauses, as you’ll see from the following sections). They need an additional clause so as to form a complete sentence and be understood.

Simple sentence

A simple sentence normally contains one statement:

The train should be here soon.

His father worked as a journalist.

Compound sentence

A compound sentence contains two or more clauses of equal status (known as main clauses), which are normally joined by a conjunction such as and or but:

Joe became bored with teachingandhe looked for a new career.
[main clause][conjunction][main clause]
Boxers can be very friendly dogsbutthey need to be trained.

[main clause]

[conjunction][main clause]

Complex sentence

A complex sentence is also made up of clauses, but in these sentences the clauses are not equally balanced. They contain a main clause and one or more subordinate clauses:

The story would make headlinesif it ever became public.
[main clause][subordinate clause]
He took up the project againas soon as he felt well enough.
[main clause][subordinate clause]

Back to sentences, clauses, and phrases index

Grammar and usage