1. Sudden and suddenly. Instead of using "sudden" or "suddenly" to make the reader feel that some action or event has just happened (or is about to), use an action or the sentence to tell your reader exactly what is going to occur. Get rid of these two words and write more descriptively instead, explaining to the reader about the surprising new plot development.
2. Very. There are so many other, better words to use in writing other than "very". Be detailed and creative when writing a piece (whether it's just for yourself or a paid project for a client) and steer clear of using "very"; for example, instead of writing "very nice", use friendly, affable, or kind.