As the results of my recent survey clearly show, the vast majority of people value grammar. Why should you care? Because poor grammar can cost you money.
You don't need to swot up on grammar rules, but it really does make sense to check what you write. Better yet, get it checked by a professional.
These are the most common mistakes I pick up when editing:
Its v it's: A very common mistake (and one that I'm guilty of making myself).
- Its: A possessive pronoun ('Company C has seen its sales plummet recently.').
- It's: A contraction of 'it is' or 'it has' ('It's Monday today.' / 'It's been nice talking to you.')
There, their and they're: Mixing these up makes for horrible, confusing writing.
- Their: A possessive pronoun ('It's their car.').
- There: Commonly used as a reference to place ('Their car is over there.') or a pronoun ('There are many cars.')
- They're: A contraction of 'they are' ('They're looking for their car over there.')
Your v you're: Pretty much equal in meaning and frequency of occurence to their and they're.
- Your: 'It's your car.'
- You're: 'You're going to regret that.'
A lot: Not alot.
Misplaced apostrophes: A simple rule I learned at school when dealing with contractions is to place the apostrophe where the missing letter should be. It's correct, easy to remember and works a treat, yet I often read things like "do'nt" or "should'nt".
Editors exist for a reason, so you shouldn't feel like a failure or stupid if you ask one to check your work. Believe me, it's worth it both in terms of your reputation and your financial health.

I'm Richard Knobbs, a writer, editor, teacher and communication consultant based in Tokyo.
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