动词 buy 可以表示 believe （相信）的意思。

    buy sth.(informal) to believe that sth is true, especially sth that is not very likely 相信（尤指不太可能的事 ）You could say you were ill but I don't think they'd buy it ( = accept the explanation). 你可以称病，但我想他们不会相信的。（摘自《牛津高阶英汉双解词典》第9版 buy 词条）

    buy [+ obj.] informal : to accept or believe (something) as true 接受；相信 He said it was a mistake, but I don’t buy it.他说这是个失误，我才不信呢。（摘自《韦氏高阶英汉双解词典》buy 词条）