1 . 有用的
... 我愿意I incline to; I am inclined to; I am willing to; I tend to 有用的useful ; of use; serviceable; good for; instrumental; productive有意義的meaningful; fulfilling.
2 . 生產性
policy to guide productiveservice industry in developed countries and its enlightenment ., 發達國家生產性服務業的政策導向及啟示.
3 . 生產的
productivezone 生產層productive生產的;開采的productivity distribution 生產力布局
4 . 富有成效
New technology helped make the expeditions more efficient and productivethan in the past ., 新技術幫助這次考察比過去的更有效 , 更富有成效.