What is a parenthesis?

A parenthesis is additional information which has been added into a sentence as an afterthought or an explanation. If a parenthesis is removed from a sentence, the sentence is still grammatically correct. 

Dashes, commas and brackets are all a form of parentheses. 

You can choose either form of parenthesis when writing. There are no strict rules about how to use them, but there are a few things to have in mind.

Commas can be easily confused with other commas in sentences. They are often used around things that flow naturally with the sentence.

Brackets are easy to identify but can look informal. They are mostly used around something that is unnecessary or background information.

Dashes are a very clear form of parenthesis. They are often used to enclose part of a sentence which interrupts the flow.


For this set of activities, you will be asked to choose which sentence has placed a parenthesis in the correct place.

Here's an example.

Which of these sentences has placed the parenthesis (my best friend) in the correct place?

a) Tristan (my best friend) is going skiing with me.

b) Tristan is going skiing (my best friend) with me.

The answer is a) Tristan (my best friend) is going skiing with me.