用when或where改写所给句子

用when或where改写所给句子
1、A:the manager who is in charge of the department wasn't in the office when the accident happened.B:the manager who is in charge of the department wasn't in the office at the time__________.2、A:these days we are busy having our social practice as packagers on an assembly line,but today we can have a good rest since the assembly line broke down yesterday.B:the assembly line __________broke down yesterday3、A:my good friend,catherine works for the company,so i want to apply for a position in the company.B:i want to apply for a position in the company__________.4、A:i'll never forget the day,because i had my interview for the first time on that day.B:i never forget the day__________.