To take very stringent security precautions
to keep a close (good) watch over
to keep a close (good) watch over
- canh gác nghiêm ngặt: to keep strict watch
- canh phòng: To watchcanh phòng biên giớito watch the bordercanh phòng cẩn mậtto watch closely; to take strict security precautions
- sự canh phòng: watchlook-out