When a mother hen makes a loud noise or crouches down, all her chicks understand this as a warning of danger.

当一只母鸡大声作响或是蜷缩蹲下，小鸡们知道这是有危险的警告。

youdao

Parents convey all sorts of messages by facial expression, intimacy, reassurance, warning of danger or encouragement and confirmation.

父母则通过表情传达疼爱、放心、警告、鼓励或者批准等种种信息。

youdao

youdao

Scaffolding was erected to bar entry into the nave, and signs were posted warning of danger overhead.

FORBES: So You Think You Wouldn't Be Bamboozled By Lothar Malskat's Art Forgeries? [Book Excerpt #2]

It was simply safer, from the point of view of survival, to hear rustling in the grass as a warning of danger.

WSJ: May 21 and the Enduring Appeal of the Apocalypse

He has also taken a hard line towards Iran, repeatedly warning of the danger to the international community of allowing it to develop nuclear weapons.

BBC: Profile: Benjamin Netanyahu