I'm the sort of person who likes to plan ahead so I'm already thinking of where to go on holiday next year.
I've been reading my way through hotel reviews on Trip Advisor and am amazed at the number of people who insist they will "defiantly" be returning next year.
I have a mental image of the hotel manager begging them not to return, only for them to shout "Ha! You try and stop me! I'm coming back next year whether you like it or not!".
Of course, they mean definitely rather than defiantly.
Definitely is one of the most commonly misspelled word in the English language. It's also commonly misspelled as definately.
One way to remember it is to tell yourself "I know I can get it right!" That should remind you that the letter "i" is used twice in it.