以下几种表达都可以表示“下定决心做某事”：make up one's mind to do sth ; decide to do sth. ; be determined to do sth. 例如：
Once he made up his mind to do sth. , nothing could stop him. 他一旦下定决心做某事，没什么可以阻止他
I had to decide first to face every pain brought upon me by others or by myself and deal with all of it. 我是不得不先下决心去面对别人或自己带给我的每一刻痛楚，然后再去应对
She was determined to do well. 她决心要做好
