The rule is: the word 'it's' (with apostrophe) stands for 'it is' or 'it has'. If the word does not stand for 'it is' or 'it has' then what you require is 'its'. This is extremely easy to grasp. Getting your itses mixed up is the greatest solecism in the world of punctuation. No matter that you have a PhD and have read all of Henry James twice. If you still persist in writing, 'Good food at it's best', you deserve to be struck by lightning, hacked up on the spot and buried in an unmarked grave.
Lynne TrussMy favorite thing in the world is a quiz show, 'University Challenge,' so you can see what kind of sad person I am.
Lynne TrussI recently heard of someone studying the ellipsis (or three dots) for a PhD. And, I have to say, I was horrified. The ellipsis is the black hole of the punctuation universe, surely, into which no right-minded person would willingly be sucked, for three years, with no guarantee of a job at the end.
Lynne TrussSticklers never read a book without a pencil at hand, to correct the typographical errors. In short, we are unattractive know-all obsessives who get things out of proportion and are in continual peril of being disowned by our exasperated families.
Lynne Truss