A girl sits at a desk and reads a paper .
The girl sitting at the desk is reading a paper .
A girl sits at a desk and reads a paper.
The girl sitting at the desk is reading a paper.
"sitting at the desk is reading a paper" is a rephrasing of "sits at a desk and reads a paper".
`` sitting at the desk is reading a paper '' is a rephrasing of `` sits at a desk and reads a paper '' .