Parenthesis: Brackets, Dashes, Commas (KS2)

Parenthesis sounds like a complicated word, but the idea is friendly. It means adding a little extra information into a sentence, then marking it off so the reader knows it is a side note. In this guide we will explain what parenthesis is, show the three ways to mark it, and share clear examples so your Year 6 child can practise with confidence.

What is parenthesis?

A parenthesis is a word, phrase or clause dropped into a sentence to give extra information. The clever part is that the sentence still makes complete sense if you take the parenthesis out again. That is the simplest test of all: if you can lift the words out and the sentence still works, it is a parenthesis.

Look at this example:

My grandad, who is eighty, still runs every morning.

The main idea is "My grandad still runs every morning." The extra information who is eighty is the parenthesis. Remove it, and the sentence is still correct, which is how we know it is a true aside rather than an essential part of the meaning.

The inserted word, phrase or clause is itself called the parenthesis. It is then enclosed by a matching pair of punctuation marks: brackets, dashes or commas. For KS2, the key point is that the marks always come as a pair, one before the extra detail and one after it.

Three ways to mark parenthesis: brackets, dashes and commas

The England National Curriculum introduces all three ways to mark a parenthesis in Year 5, and pupils build on them in Year 6. They are:

• a pair of brackets
• a pair of dashes
• a pair of commas

The most important rule is that you must use a matching pair. If you open with a bracket, you close with a bracket; if you start with a comma, you finish with a comma. Never mix them. Here is the same parenthesis shown all three ways:

• The cake (baked by my aunt) vanished in minutes.
• The cake - baked by my aunt - vanished in minutes.
• The cake**, baked by my aunt,** vanished in minutes.

Each version is correct. The choice comes down to how much you want the aside to stand out.

Using brackets to add extra information

Brackets are a neat, quiet way to tuck in a small fact or comment. They tell the reader, "this is a useful extra, but you could skip it." In KS2 we use round brackets, ( and ). Here are some examples:

• The Romans invaded Britain (in AD 43) and stayed for centuries.
• Our school trip (to the Natural History Museum) is next Tuesday.
• Sophie (my oldest cousin) is learning the violin.

Notice that the closing bracket comes before the full stop at the end of a sentence, like this: We won the quiz (only just!). The extra information lives entirely inside the brackets, so the sentence outside still reads smoothly. Brackets are especially handy for dates, quick definitions and little asides you want to keep in the background.

Using a pair of dashes for parenthesis

A pair of dashes does the same job as brackets, but with more of a flourish. Dashes make the extra information stand out, so writers often choose them when the aside is surprising or dramatic:

• The treasure chest - and you will not believe this - was completely empty.
• My little brother - usually so shy - sang on the stage.
• We finally reached the summit - exhausted but thrilled - as the sun rose.

Two dashes are needed, one on each side, just as with brackets. Dashes give writing a lively, confident feel, so they are a lovely tool to add once commas and brackets feel secure.

Using a pair of commas for parenthesis

A pair of commas is the most common way to mark a parenthesis, and it suits a short, gentle aside. The trick that catches many pupils out is remembering both commas: one before the extra information and one after it.

• Our head teacher, Mrs Patel, gave a speech.
• The football, soaking wet, slipped from his hands.
• Venus, the second planet, is the hottest in our solar system.

If you forget the second comma, the sentence loses its balance, so always check that the extra detail is fenced in on both sides. Our guide to using commas at KS2 explores this further, and it is the same comma rule used around a non-essential relative clause, such as "My bike, which is bright red, has a flat tyre."

A quick word on choosing. Commas suit most short asides, brackets are quietest and good for facts, and dashes are boldest and add drama. For the SATs, the safest rule is to use a matching pair and check that the sentence still works once the parenthesis is removed.

How parenthesis is tested in the KS2 SPaG paper

In the Year 6 SPaG test, parenthesis can appear in several ways. Pupils might be asked to:

• add a pair of brackets, dashes or commas to show the parenthesis in a sentence,
• choose the sentence that uses brackets, dashes or commas correctly,
• name the punctuation used to mark the parenthesis, or
• insert the missing second mark when only one has been given.

Questions often check that pupils use a matching pair and place both marks correctly, so that is well worth practising. Our guide to colons and semicolons at KS2 is a useful companion, and for an overview of the paper see what the SPaG test involves. Exact test dates and arrangements can change each year, so always confirm the latest details on GOV.UK.

Practice: add a parenthesis three different ways

A great way to learn parenthesis is to take one plain sentence and add the same extra information three ways. Try this together, saying each version aloud. The plain sentence is My teacher read us a story and the extra information is a tale about dragons.

1. With brackets: My teacher read us a story (a tale about dragons) before lunch.
2. With dashes: My teacher read us a story - a tale about dragons - before lunch.
3. With commas: My teacher read us a story**, a tale about dragons,** before lunch.

Then check each one by removing the parenthesis. "My teacher read us a story before lunch" still makes complete sense every time, which proves the extra information really is a parenthesis. Practising this swap is exactly what builds confidence.

How SATS LION helps

SATS LION turns parenthesis and the rest of KS2 SPaG into short, friendly challenges inside Word Mage Academy, so your child practises placing brackets, dashes and commas without it feeling like a worksheet. Every question is matched to the England National Curriculum and gently revisits tricky ideas like remembering the second comma.

Curious to see how it works? Take a look at what is inside SATS LION.