A price policy can influence people's choice on short journeys, at the same time it will reduce the unnecessary long flights, so could be an effective method to improve the environment conditions.

用价格机制去影响人们对中短途旅行的选择，同时减少不必要的远程旅行，是很有效的环境经济手段。

youdao

When I've been needed so much for such a long time, it's hard to step back and feel unnecessary.

在我被如此需要了这么长一段时间之后，很难退一步，并且觉得自己是多余的。

youdao

Health care-associated infections have long been established as the biggest cause of avoidable harm and unnecessary death in the health systems of high income countries.

长期以来，卫生保健相关感染一直是高收入国家卫生体系中存在的可避免伤害以及出现不必要死亡的最大原因。

youdao

For too long, unnecessary differences between U.S. and Canadian regulatory approaches have posed hurdles for our businesses and increased costs for consumers.

WHITEHOUSE: The United States and Canada Announce Progress in Regulatory Cooperation | The White House

Unnecessary stimulus with serious long-term consequences Mr Greenspan and others worry that budget deficits will crowd out private investment and force up interest rates would only add to the structural imbalances in the American economy.

ECONOMIST: Taxing times | The

He has long opposed it as unnecessary and unfair.

WHITEHOUSE: Press Briefing