purposeful
adj. 有明确目标的，坚决的；故意的，蓄意的；有意义的
例句
She looked purposeful and determined.
她看来胸有成竹、意志坚定。
《牛津词典》
Purposeful work is an important part of the regime for young offenders.
使从事有意义的劳动是管理少年犯的重要方法。
She had a purposeful air, and it became evident that this was not a casual visit.
她一副志在必得的样子，显然这不是一次随意造访。
《柯林斯英汉双解大词典》
