Grammar - That, Which or Who

Another common confusion is whether to write that, which or who in a sentence and what each actually means.

It’s all relative

The words which, who and that are all relative pronouns and they are used in sentences to introduce relative clauses. As they are relative pronouns, the word who must only refer to actual people and the word which can only refer to things or possessions. The word that can in fact be used to refer to people and to things.

As you are writing your sentence, determine whether or not you know what it is that you are actually talking about. So in the sentence “I can’t find my book that I was reading today”, the word that tells whoever is listening or reading the information they need to know what book you are referring to.

In the sentence “’this book which I bought today is brilliant”, the word which introduces a new piece of information to the reader or the listener. In these particular sentences the use of the word that is incorrect.

Using that instead of which

After words such as something, everything, all and after the described thing, you would normally use the word that rather than the word which.

Something that astounds me every time is...

Everything that I own is in this room.

All that will be left in the bedroom is the carpet.

Using which instead of that

In circumstances that the relative pronoun refers to the entire previous clause, and not only just the noun that comes after it, that shouldn’t be used. So when these circumstances arise, you use which instead of that.

The man down the street fathered 10 children which is amazing for his age.

Using which or that when using commas

When looking at information that is deemed unessential or additional and separated by commas you would normally use the word which. Using the word that is uncommon in these situations and unusual. Take a look at the sentences below to see what I mean:

I lent her the picture book and the first word book, which are easy to read.

The fast food outlet, which serves chicken and turkey, was closed last year.