同时开始

start simultaneously

同时发生的现象

phenomena that occur simultaneously

同时并举

develop at the same time

这是同时发生的。

This happened at the same time.

我们要在继续提高产品质量、增加品种的同时，大大地增加产量。

While continuing to improve quality and add products, we want to greatly increase production.

他们是学生，同时又是先生。

They are students, and also teachers.

这是非常重要的，同时也是十分艰巨的任务。

This is an extremely important and highly difficult task.