She would not travel by air for anything.前边为什么用would?

这里的would 不是过去分词
是情愿的意思, 全局意思是她情愿不坐飞机旅行, 不管是为了什么事.
助词 v.aux.
1.
(will的过去式,表示过去将来时)将
She said she would come.
她说过她会来的.
2.
(表示意志)愿,要;偏要
I told her to stop nagging, but she just wouldn't listen.
我叫她别再唠叨,可她就是不听.
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