"Since I appointed a new department head, business has certainly improved." the boss smiled." The new fellow keeps an eagle eye on all aspects of our operations. He watches the staff with an eagle eye, too." Someone with an eagle eye watches things closely and carefully. Nothing escapes his attention.
“自从我任命了一个新的部门主任后，公司业绩大幅提高，”老板得意地说“这个新人对公司的各项工作都认真负责，对员工的督促监管也很严厉，眼睛像鹰般敏锐。”
鹰(eagle)有极佳的眼力，纵然盘旋于高空上，也能看见地下细小的猎物，于是给了我们"an eagle eye"这个用语，比喻某人有锐利的目光。