role of the writer (Lord Of The Rings)

Making larger roles for the female characters s in the film

to keep the audience interested and also appealing to the modern audience and they also gave the females a very strong role to play in the movie in order to balance it out for example Arwen playing a love scene 

Taking out (omitting) certain characters in the film look at this site for help

some characters were taken out example Tom Bombadil was taken out due to little parts of the movie he had that didn't move the movie

Writing an exposition (what has happened before the film starts) scene for the beginning of the film

an exposition is an explanation of what happens in the movie for the audience to be able to understand some of the drastic bit  that might be hard to follow up for example when Gandalf made a exposition of the ring to tell us the story of the ring 

Working with the actors as characters to create some parts of the script. 

Some of the actors were interviewed for instance the dwarfs were called in and asked question about their life style and what they would reply to certain parts of the scripts. Sometimes the writer depends on the actors for ideas on what to say