健康资讯 我想问下空调上的AC还有最后一个DUAL是什么意思？还有就是内循环和外循环要在什么时候开才对呢？
dual responsibility
和
due responsibility
1，Dual 的意思是"双重的"，注意它的发音是/'du:əl/，所以dual responsibility是"双重责任"。
例如: Today, the U.N. has a dual responsibility: to help Iraq forge a better future — and to leave Iraq to Iraqis.
2，Due 的意思是,"到期的，应得的", 其发音是/'du:/,和上面那个发音非常相似。due responsibility是"应尽的责任"。
例如: To respect and take good care of old parents is our due responsibility
河北正定古城
