on high alert 高度戒備

on high alert
繁：高度戒備
简：高度戒备

除了前任總統特朗普缺席之外，今次就職儀式的安排和規模因應新冠病毒疫情和國會衝擊事件跟以往很不同，華盛頓進入高度戒備，大批民眾未能到現場出席典禮，而傳統的就職舞會和國會午宴都要取消。

拜登宣誓就任美國第46任總統　承諾與其他國家恢復合作（2021年1月21日）。Now新聞，取自 https://news.now.com/home/international/player?newsId=421076

The development comes as tens of thousands of Guardsmen and federal agents remain on high alert in Washington in an unprecedented show of force that has transformed the nation’s capital into a veritable military fortress.

Washington on High Alert on Eve of Biden Inauguration. (2021, January 19). Voice of America. Retrieved from https://www.voanews.com/usa/washington-high-alert-eve-biden-inauguration