对某事认真be serious后面用什么介词

对某事认真be serious后面用介词about 。be serious about 是固定搭配。

例如，他对自己的学习和生活一贯很认真，即使在业余时间里，他也非常严格执行自己制定的学习计划。

For example, he has always been very serious about his study and life, and even in his spare time, he is very strict with his study plan.

be serious 后边加about 表示对某事认真。例如

Here's the signs that your guy might not be serious about you.  

以下的迹象表明你现在的男朋友并没有对你认真

I think you should be more serious about your business.  我想你应该对工作更上心。

You seem to be very serious about helping your employees.  

看起来公司是真正的在帮助员工。