1
It be presumptuous of sb to do sth
此句型用 it 作形式主语，of sb 表示行为主体，to do sth 说明具体行为。
It would be presumptuous of me to speak for the whole team.
我替整个团队发言就太冒昧了。
冒昧的；放肆的
先理解核心含义，再看它在真实句子里的用法。
冒昧的；放肆的
Showing too much confidence and behaving or assuming things beyond what is appropriate or rightful; taking unwarranted liberties.
It would be presumptuous of me to speak for the whole team.
我替整个团队发言就太冒昧了。
做出无根据的假设或臆断,常因傲慢或过度自信而超越适当或正当的界限
Making unwarranted presumptions or assumptions, often out of arrogance or excessive self-confidence, and thus exceeding appropriate or rightful limits.
过分冒失的
excessively forward
It was presumptuous of him to assume he would get the promotion without even applying.
他连申请都没提交就认为自己会得到晋升，真是太冒失了。
AI contextual example
She felt it was presumptuous to ask her boss for a raise after only two weeks on the job.
她觉得才工作两周就向老板要求加薪太过放肆。
AI contextual example
Calling him by his first name without permission seemed presumptuous to the new intern.
未经允许就直呼其名，在新来的实习生看来十分无礼。
AI contextual example
the duchess would not put up with presumptuous servants
公爵夫人无法容忍放肆的仆人。
WordNet
此句型用 it 作形式主语，of sb 表示行为主体，to do sth 说明具体行为。
It would be presumptuous of me to speak for the whole team.
我替整个团队发言就太冒昧了。
主语是人时，表示某人做某事显得冒失或越界；语气比 it 句型更直接。
He was presumptuous to question the manager's decision.
他质疑经理的决定，太放肆了。
in doing sth 强调在做某事的过程中表现出的冒失态度。
She was presumptuous in assuming she would be invited.
她擅自假定自己会被邀请，实在冒昧。
Not this
He presumptuous to ask such a personal question.
Use this
He was presumptuous to ask such a personal question.
presumptuous 是形容词，作表语时必须与系动词 be 连用，不能像中文“他冒昧”那样直接省略 be。这里描述的是过去的行为，因此用 was。
Not this
It was presumptuous for him to ask such a personal question.
Use this
It was presumptuous of him to ask such a personal question.
在 It is + 形容词 + of/for sb. + to do 句型中，presumptuous 这类评价人品性或行为的形容词后应用 of 连接人，表示“某人这样做是冒昧的”；用 for 则语义不符合这种评价结构。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
某人做某事很冒昧
It was presumptuous of him to assume she would lend him the money.
他擅自假定她会借钱给他，实在是太冒昧了。
冒昧的行为；放肆的举止
His presumptuous behavior at the meeting annoyed everyone.
他在会上冒昧的举止让大家都感到不悦。
放肆的话；冒昧的言论
She apologized for her presumptuous remark about his private life.
她为自己对他私生活的冒昧评论道了歉。
无根据的臆断；自以为是的假设
It would be a presumptuous assumption to think the project will succeed without proper planning.
认为没有适当规划项目就会成功，是一种自以为是的臆断。
显得冒昧；显得放肆
I don't want to seem presumptuous, but may I offer some advice?
我不想显得冒昧，但我可以提点建议吗？
Use presumptuous naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
联想 presume（假定）：别人还没同意，他就先假定可以，实在冒昧放肆。
语域：formal 常见场景：正式写作、文学评论 presumptuous 多用于正式或书面语境，指言行冒失、超出适当界限，语气较审慎，日常口语中相对少见。
形容词，不可直接接宾语；常用结构为 be presumptuous of someone to do something
Dictionary facts from ECDICT, WIKTIONARY.