Date Posted : Apr 24, 2011 
Writing Tips
Written by : vbahoura
That and Which: Interchangeable or Not?
Many writers use the words that and which interchangeably – as if they mean the same thing or tackle the same task within a written work. While either may sound correct within a body of words, it is important to understand the role each word plays.
Take a look at the following table and discover the difference between that and which:
| Term | Usage and Example |
| That | The word that is used to introduce information within a sentence that cannot be omitted because it would then alter or lessen the meaning of the sentence.
Example 1: Eating a variety of foods that are packed with nutrients is good for your brain and body. |
| Which | The word which (set apart with commas) is used when there is extra information in the sentence, but can be omitted without changing or lessening the meaning of the sentence.
Example 2: Eating a variety of foods, which are packed with nutrients, is good for your brain and body. |
Looking at the above two examples, you can note that in Example 1 the author finds it important to mention that eating a variety of foods packed with nutrients is good for your brain and body. Meanwhile, the author in Example 2 is simply providing you with extra information (foods packed with nutrients); the author finds that it is enough to mention that eating a variety of foods is good for your brain and body.
Always remember that there are exceptions to every rule. There may be times where which will be used to introduce important information without being set apart by commas.
Posted under : Writing Tips