Basic Punctuation

The Sentence

There are three main punctuation marks in English. They vary in strength.

  • The comma , is the weakest
  • The semi-colon ; is medium strength
  • The full stop (or period) . is the strongest
    Full stops and commas are the most important punctuation marks to master.
  • The only other essential mark is the question mark ?:
    "What time is it?"
    "She is leaving soon, isn't she?"

The reason we use punctuation is to make the structure of our writing clear. This helps the reader understand what we want to say.

The passage below is hard to understand because it contains no punctuation. Try to read it now:

the harbour looked peaceful in the twilight a few boats bobbed at anchor the last of the seagulls wheeled overhead sarah gazed down into the dark waters something white caught her attention very slowly it was rising to the surface

How did you get on?

The structure of the passage is not clear. Did "something white" catch Sarah's attention very slowly or did it rise to the surface very slowly? Who was overhead - Sarah or the seagulls? If you try to read the passage aloud, you will not know where to pause. The meaning will be unclear too.

The meaning of the passage becomes clearer when the commas and full stops are added.

The harbour looked peaceful in the twilight. A few boats bobbed at anchor. The last of the seagulls wheeled overhead. Sarah gazed down into the dark waters. Something white caught her attention. Very slowly it was rising to the surface.

We have now broken the passage up into a series of units. Each one begins with a capital letter and ends with a full stop ( . ).

These units are sentences of English.

The harbour looked peaceful in the twilight.
A few boats bobbed at anchor.
The last of the seagulls wheeled overhead.
Sarah gazed down into the dark waters.
Something white caught her attention.
Very slowly it was rising to the surface.

All of these sentences have something else in common.

Each sentence is about something.

Each sentence describes some kind of action, state or activity.

The harbour looked peaceful in the twilight.
A few boats bobbed at anchor.
The last of the seagulls wheeled overhead.
Sarah gazed down into the dark waters.
Something white caught her attention.
Very slowly it was rising to the surface.

This is the basic structure of an English sentence.

There are three main punctuation marks in English. They vary in strength.

  • The comma , is the weakest
  • The semi-colon ; is medium strength
  • The full stop (or period) . is the strongest

Punctuation helps to clarify the structure of sentences. In particular, it identifies the grammatical units from which sentences are formed. The passage below is hard to understand because it contains no punctuation. Try to read it now:

the harbour looked peaceful in the twilight a few boats bobbed at anchor the last of the seagulls wheeled overhead sarah gazed down into the dark waters something white caught her attention very slowly it was rising to the surface

How did you get on?

The structure of the passage is not clear. Did "something white" catch Sarah's attention very slowly or did it rise to the surface very slowly? Who was overhead - Sarah or the seagulls? If you try to read the passage aloud, you will not know where to pause. The meaning will be unclear too.

The meaning of the passage becomes clearer when the commas and full stops are added.

The harbour looked peaceful in the twilight. A few boats bobbed at anchor. The last of the seagulls wheeled overhead. Sarah gazed down into the dark waters. Something white caught her attention. Very slowly it was rising to the surface.

We have now broken the passage up into a series of units. Each one begins with a capital letter and ends with a full stop ( . ).

These units are sentences of English.

The harbour looked peaceful in the twilight.
A few boats bobbed at anchor.
The last of the seagulls wheeled overhead.
Sarah gazed down into the dark waters.
Something white caught her attention.
Very slowly it was rising to the surface.

All of these sentences have something else in common.

Each sentence has a subject. This is usually a noun, a pronoun, or a noun phrase. The subject is what the sentence is about.

Each sentence contains a verb or a verb phrase. This describes some kind of action, state or activity.

The harbour looked peaceful in the twilight.
A few boats bobbed at anchor.
The last of the seagulls wheeled overhead.
Sarah gazed down into the dark waters.
Something white caught her attention.
Very slowly it was rising to the surface.

Noun phrase plus verb phrase is the basic structure of an English sentence.

Sentences may also contain other elements:

Something white caught her attention.

The second noun phrase is called the object of the sentence.

The harbour looked peaceful in the twilight.

Above, peaceful is an adjective.

The last of the seagulls wheeled lazily overhead.

Very slowly it was rising to the surface.

Lazily, overhead, very and slowly are adverbs.

The harbour looked peaceful in the twilight.

A few boats bobbed at anchor.

Sarah gazed down into the dark waters.

Very slowly it was rising to the surface.

These are all prepositional phrases.

Exercise

Read the following paragraph and decide where the punctuation should go. Tap the dotted square at the end of each sentence to place a full stop. Tap the following word to give it a capital letter.

Sarah was caught between curiosity and fear she knelt down on the cold stone of the harbour wall the mysterious white bundle had almost surfaced a sudden wave pushed it against the wall it broke open a scream of terror assaulted Sarah's ears 

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