acknowledge 的核心是「公开承认某事的存在或真实性」——可以是承认事实（acknowledge a mistake），可以是表示感谢（acknowledge sb.'s help），也可以是回应确认（acknowledge a letter）。三个义项都指向同一个动作：正式地给出回应，承认某事的存在。与 admit 的区别：admit 含「不得不」的被迫感，acknowledge 更中性、更正式。
释义
1
v.承认（某事为真）
The company finally acknowledged that the product had safety issues.
公司终于承认产品存在安全问题。
2
v.致谢；表示感谢
In her speech, she acknowledged the support of her team.
在演讲中，她感谢了团队的支持。
3
v.回应；确认收到
Please acknowledge receipt of this email.
请确认收到此邮件。
语感
acknowledge = 中性承认，admit = 被迫认错，confess = 认罪
承认致谢确认
三词都可译「承认」，但情感色彩截然不同：acknowledge = 中性地公开承认，不含被迫或羞耻感（acknowledge a fact）；admit = 承认令人不快的事，有「不得不承认」之感（admit a mistake）；confess = 坦白罪行或秘密，含强烈的道德重量（confess to a crime）。高考作文论述中，「承认某现象的存在」优先选 acknowledge。
陷阱
⚠️acknowledge + that 从句
✗
He acknowledged to have made an error.
他承认犯了一个错误。
acknowledge 后接 that 从句，不接 to have done；acknowledge doing 也可，但 to do 是错误
✓
He acknowledged that he had made an error.
他承认自己犯了一个错误。
⚠️acknowledge vs admit 语气差异
✗
The scientist admitted that his research had broad implications.
这位科学家承认他的研究有广泛影响。
admit 带「被迫、不情愿」语气，承认积极的/中性的事实用 acknowledge 更恰当
✓
The scientist acknowledged that his research had broad implications.