a narrowly defined task的用法和样例：
- That may sound like a narrowly defined niche to have its own series of job-search sites, but it's part of a growing number of sites dedicated to matching employers and job seekers in very specific pockets of the job market.
- Women today find themselves in an intense battle with a society that cannot let go of a narrowly defined word ethic that is supported by a family structure that has not existed for decades.
- A gem cut in the form of a narrow rectangle.
- A narrow border, molding, or fillet.
- He has only a narrow circle of friends.