sentinel

哨兵、衛兵、警衛

Two sentinels stood at the gate throughout the night.

兩名哨兵整夜守在大門口。

守護者、看守者文學

Tall pines rose like silent sentinels along the ridge.

高大的松樹像沉默的守護者，矗立在山脊上。

警示指標、預警訊號正式

Doctors treat the infection as a sentinel for wider outbreaks.

醫師把這個感染視為大規模疫情的預警訊號。

守衛、警戒正式

Guards sentineled the palace entrance around the clock.

警衛全天候守衛著皇宮入口。