sining off 塞林奥夫。听了这个发音不知道英文和中文意思

是signing off吧……
有注销，退出，下课等意思。

signing off?

Sign-off (or, in British/Irish/New Zealand English, closedown) is the sequence of operations involved when a radio or television station shuts down its transmitters and goes off the air for a predetermined period (most commonly during the overnight hours). Sign-off is the reverse process to a broadcast sign-on.

就是说她要下线关机了。

sign off 广播完毕 签字发誓戒绝, 废除; 断绝; 停止 在考勤簿上签下班时间
这里是signing off 广播完毕

signing off----------- 电台停止广播

你确定是这样拼吗