sign通常用作数学符号、物理符号等。signal就是一种向进程传递信息的方式,可以将信号想象成大楼的管理员往房间的信箱里塞小纸条。
He signaled the waiter to bring the menu.
他做手势要侍者拿菜单来。
The conductor signaled the orchestra to rise.
指挥打手势让乐队起立。
Jim signaled his helplessness to Mary to leave the party.
吉姆无法从宴会脱身时,他向玛丽使了个眼色,表示无可奈何。
She had a silver peace symbol hanging on a chain around her neck.
她有一个银制的和平标志挂在项链上。
She put her finger to her lips as a sign to be quiet.
她将手指放在唇上表示应安静。
He gave his wife a ring as a token of his love.
他给他爱人一枚戒指,作为爱情的象征。