听觉能让人类对食肉动物爬近有所警惕，准备进攻。

Hearing could alert to a predator creeping up, ready to attack.

youdao

在一封“休伯特”写给“珍妮特阿姨”的信中，将信中的首字母串在一起就是：“14架‘波音堡垒’战斗机昨日飞抵伦敦，准备进攻基尔（德国）。”

The code was used in a letter from "Hubert" to "Aunt Janet" to conceal the message: "14 Boeing Fortresses arrived yesterday in Hendon (London). Pilots expect to raid Kiel (Germany)."

youdao

武装部队已准备好击退任何进攻。

The armed forces were prepared to repulse any attacks.

《柯林斯英汉双解大词典》