Julie L Gray is the writer of one of my favorite blogs "The Rouge Wave". Her post from 10th of August is realy great. There is such a good example of how not to write. Rather then me quoting her, you can read the article for yourself here:
The Rouge Wave: Bad Action Line, Bad!
I have read many movie scripts. Most of them from amateurs. And all too many from bad amateurs. I have read lines like "He has stayed in the house for all his life, living with his mother." How do we see that? That is a line suitable for a novel. In a movie we must be shown or told through dialog.
I thought that I had overcome these novice misstakes when I got the feedback "How do we know the water is cold?" It is sometimes difficult to avoid, but he was right. I shouldn't write about cold water, I should describe the reaction to the coldness or if no one swims the general appearence of the lake. If it is important that is.