当真做某事用英语怎么说

在英语中，"to mean business" 意味着认真对待某事，并决心要做到成功。这个表达来源于俚语，常被用来形容一个人对某事非常认真、专注、决心。
例句：
She means business when it comes to getting the job done. (她在做事情时是认真的。)
He means business when he sets his mind to something. (他在做事情时是认真的。)
I can tell that she means business by the way she talks and acts. (我能从她的谈话和举止中看出她是认真的。)