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有意义的meaningful; fulfilling.
2 . 生产性
policy to guide productiveservice industry in developed countries and its enlightenment ., 发达国家生产性服务业的政策导向及启示.
3 . 生产的
productivezone 生产层productive生产的;开采的productivity distribution 生产力布局
4 . 富有成效
New technology helped make the expeditions more efficient and productivethan in the past ., 新技术帮助这次考察比过去的更有效 , 更富有成效.