Sentry duty
na. 步哨勤务\\n
🧩 词语组成解析
sentry
['sɛntri]
n. 哨兵;警卫;
🗣️ 情景例句
You'll do great. break a leg!
你会干得很棒的，祝你好运！
Every medal has its reverse.
事物都有它的反面。
It is fairly clear that sleeping period must have some function,
很清楚，睡眠必然具有某种作用。