An easy one today: when should you use who’s and whose? This is pretty straightforward, and I think most mistakes people make with them are generally typos caused by the two sounding similar. But I do notice quite a lot of mistakes with these words in people’s writing. First, let’s look at some examples of both being used correctly:
Whose phone is this? I found it over there.
That’s the guy who’s living in the apartment opposite me.
That’s the guy whose apartment is opposite mine.
Who’s coming to visit you?
My friend, whose family are from France, is coming to visit today.
OK, I think just from looking at those you can probably get a sense for the difference, but let’s look at the grammar quickly.
Whose is the trickier one to define. It’s a pronoun or determiner, generally used to refer to an object possessed by someone, or an aspect of something. Another way to think about it is that its like the possessive form of who. Be careful though, because it’s not always used to refer to a person, e.g. Name a country whose flag contains three colours.
Who’s is actually much more straightforward: it’s always a contraction of who is. Because who and is are both such common words, there are so many different occasions in which you can use who’s that there’s no point in telling you when to use it. The simplest thing to do, if you’re not sure if you need to use who’s or whose, think about whether you can replace the word with who is. If you can, use who’s, and if you can’t, use whose!