Electronic sentry
[计] 电子报警器, 电子哨兵
🧩 词语组成解析
sentry
['sɛntri]
n. 哨兵;警卫;
🗣️ 情景例句
Don't litter.
请不要乱扔东西。
Keep thing seven years and you will find a use for it.
备而不用。
You can either stay or leave.
你或者留下或者离开。