QUESTION: Fix punctuation: Choose the model you like best to present it
ANS: Choose the model you like best to present it.

QUESTION: Fix punctuation: Before you can open a CNDF file youll need to figure out what kind of file the CNDF file extension refers to
ANS: Before you can open a CNDF file, you'll need to figure out what kind of file the CNDF file extension refers to.

QUESTION: Fix punctuation: But at the garret window stood the young girl with sparkling eyes and the rosy hue of health on her cheeks and she folded her delicate hands over the pea blossom and thanked our Lord for it
ANS: But at the garret window stood the young girl with sparkling eyes and the rosy hue of health on her cheeks, and she folded her delicate hands over the pea blossom and thanked our Lord for it.

QUESTION: Fix punctuation: 23 September 200723 September 2007 Lisa
ANS:
23. September 200723. September 2007 Lisa