She often watches the news for half an hour,and then goes to read the books ( )her work.用什么介词in 还是 on 还是with 还是to为什么

She often watches the news for half an hour,and then goes to read the books ( )her work.用什么介词
in 还是 on 还是with 还是to
为什么

in
in one's work 在上班时,在工作期间