There are mainly two structures of CNC'S RTOS. They are foreground-background type and interrupt type.
计算机数控的操作系统目前主要有前后台型及中断型二种结构。
2
For example, a film-maker might opt to include the background sound of an ambulance's siren while the foreground sound and image portrays an arguing couple.
例如，电影制作人可能会选择在背景中加入救护车的警笛声，而在前景的声音和图像中表现一对争吵的夫妇。
3
By blurring objects in the foreground, background or by blurring the entire design, you can dramatically increase the impact of your project.