Kono onnanoko wa kireina desu.
このうおんあのこわきれいなです。
Sentence structure is correct.
1.Time
2. person/object
3. what you have to say about the object.
if you all need more help one place that a Japanese friend of mine on Facebook directed me to is
A better way to learn. - iKnow!. It night help you more with seeing sentence stucture and learning to read charaters.
Hope this helped.
ばいーばい。
さよおなら。