When to use it's and its
What's that apostrophe for?
This is one of the most common word choice dilemmas that people admit to - many struggle with that apostrophe. Exactly when do you use it and when do you leave it out?
Here the apostrophe signals that a letter (or letters) has been left out: either i or ha.
it's = it is or it has
I think it's time for a cup of tea. It's been a long day.
So you use it's with an apostrophe as shorthand for it is or it has.
When do I leave the apostrophe out?
When 'its' is used without an apostrophe, it means 'belonging to it'.
The dog lost its collar.
The dog lost the collar belonging to it.
Of course, we would never say such a clumsy sentence, which is why we use its.
We get confused because when we talk about something belonging to someone (possession), we usually do use an apostrophe:
I love going to Anna's house.
This is what causes so many problems - unfortunately there's no logic to it and we just have to accept that English is full of inconsistencies!
How do I remember the difference?
The key to remembering this particular rule is to always ask yourself:
Can I say it is or it has instead of its?
If the answer is yes, put that apostrophe in there.
If the answer is no, bin the apostrophe!
There is never any other time you would use an apostrophe with its.
And if you remember that the apostrophe is used in place of letters, you'll know exactly where the apostrophe goes - between the t and the s.
The apostrophe doesn't go after the s - its' is never used in English.
So there you go - the difference between it's and its. I hope that was useful for you - if you've any other ways of remembering this rule, be sure to let me know!
Is there a grammar point you're not clear on, or punctuation mark you're not sure you're using correctly? Let me know in the comments and I'll do my best to explain.