The writing style depends on your subject. Oxford (academic style) is reserved for essays/books/magazines and basicly academic dissertations. While Associated Press (news agency style) is used for short articles/news and is focused clearly on the message you want to get with to your audience. When you write a news it is essential to use short sentences and squeeze as much content as you can in small amount of words...You also have to answer in first two sentences- who,what,where and when happened a situation you writing about...Every other sentence should be additional what means that cutting words/sentences from the bottom of your text should not deprive it the meaning/your message.
The academic style can be more decorative and colorful- it is not only important what you writing about but also how you writing (what is your style). In news agency style you rather don't use adjectives.
Choosing a right style and not mixing it with another evidence your consistency and easiness of reading.
by
Fatema Abulaila , English Intructor , Royal Jordanian Air Academy
well, you should try to stick to one writing style so that you will always have a certain way that is well known to you... but sometimes when you are writing an essay you may be restricted to using a way that isn't known to you... this happens when the side you are writing to tells you what to use in your writing... :)