英语翻译

问题描述:

英语翻译
Frequent fliers are often flying blind when it comes to knowing which airline consistently offers free seats in exchange for their hard-earned miles.
in exchange for their hard earned in exchage for hard earned blind = not knowing?

译文:当提到某一家航空公司为辛辛苦苦赚到足够飞行里数的乘客提供免费座位的情况时,即使是飞机上的常客也经常摸不着头脑.
“blind” 是“眼盲的”,这里引申为“一头雾水”.in exchange for 意为“交换”,hard earned miles “他们辛辛苦苦挣来的飞行里数”