放棄
close the book on sth
(因相信不會成功或沒有結論而)放棄
to stop doing sth because you no longer believe you will be successful or will find a solution
The police have closed the book on the case (= they have stopped trying to solve it).警方已經放棄偵破此案。
釋義來自《牛津高階英漢雙解詞典》第 9 版