Questions on Garminfone Text Message.?

I have the Garminfone and i have a problem texting. How do you turn off auto-fill for text messaging. Everytime i am texting i am frustrated with not being able to short-txt words like "ur" for "your" or "ic" for i see. it will fill in their own words that they think its right. Which it is, but i just like to type it in the way i type it. so how do you turn it off?