alpha and omega造句

1、What is the alpha and omega of affairs?
事情的来龙去脉是什么?.

2、He knows the alpha and omega of his job.
（他非常精通本职工作。）

3、She knocks on door to want to inquire a condition, but the alpha and omega unmanned reply.
她敲门想询问情况，但始终无人应答。