If you describe someone or their behaviour as presumptuous, you disapprove of them because they are doing something that they have no right or authority to do.
例句
It would be presumptuous to judge what the outcome will be.现在就判断结果将会怎样未免有些冒昧。
英汉词典释义
adj.
自以为是的,专横的;冒失的
It was presumptuous of him to take charge.他自拿主张, 太放肆了。
英英词典释义
Adjective
1. excessively forward;
"an assumptive person""on a subject like this it would be too assuming for me to decide""the duchess would not put up with presumptuous servants"