to whistle

sentinel

garish; gaudy

to keep watch; to do sentry duty; to be on patrol

whistle

lookout post; sentry post; sentry

outpost; (fig.) front line

a whistle; sentry

to blow a whistle; to whistle

border sentry post

watchhouse; sentry post

a whistle

to whistle (with fingers in one's mouth); nowadays written 呼哨

to whistle (with fingers in one's mouth); nowadays written 呼哨

hidden sentry post

to check the sentries

sentry; sentinel

dog whistle; (fig.) dog whistle (in politics)

to go on sentry duty; to stand guard

to blow a whistle; (fig.) (of a sporting event) to kick off; to get underway

(soccer etc) corrupt officiating; dubious call

skirmish

whistleblower

whistling sound

whistle given as a secret signal

inspection post; checkpoint

lookout post

sentry post

both covert and undercover (officers) keeping watch (idiom)

gaudy; flashy (but without substance)