“ would rather…than结构里，需要注意前项和后项的对称，即than所连接的词项需要与前面的词项在词性或结构上相一致。
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6. McCarthy, though Iliked him, gave me the impression he'd rather be home reading St. ThomasAquinas than going into a tar-paper shack to see how poor people livedor flying halfway around the world to speak against racism. 尽管我喜欢麦卡锡，但他给我的印象是，他宁愿坐在家读读圣托马斯·阿奎那也不想走进搭着油毡的棚子，亲眼看看没钱人是怎么样生活的，或是飞行半个地球的里程，去发表反对种族主义的演讲。（《我的生活》）”
[问]:老师们, 可以看作than后面省去be on business之意吗? 总是想成,对比be home不是要go into a tar-paper shack to see…,但如此就非常难说结构对称了.
你提到“ would rather…than“结构里，需要前项和后项的对称，我感觉也应该是如此，它和rather than（不分隔）的使用方法不同，后者可以接不定式或动名词。我曾看到海外英语平台谈到这个问题的讲解：When you use the structure: I would rather X than Y, then X and Y must match in grammatical terms. So we can say: I would rather swim than go to the party.
https://english.stackexchange.com/questions/286011/would-rather-do-than-doing
但，假如有省略成分，则形式上未必对等。如：I'd rather have hot weather than cold. (牛津实用英语语法298词条）。但你的问题句，我感觉理解为be on business的省略不适合，应该把going改为go更适合，还有后面的flying 同时改为fly. 作者如此用，或许是强调和reading St. Thomas Aquinas对比的原故，却忽视了语法规则。
