高考阅读内遇到的问题，A bird sitting on a tree is never afraid that the branch will break because its trust is not on the branch but on its own wings.查了很多版本的原题，都是使用on。求助各位大神，是否有更深一层的理解。
...必须加定冠词吗？有些词典在词条下直用the countryside这样的黑体字，说明它的结构是固定的，或者说这个定冠词是必不可少的。但是我看到有下面这样的句子：Our countryside is disappearing at an alarming rate. 我们的农村地区正在以惊人...
The rolling foothill country of north Georgia was plowed in a million curves to keep the rich earth from washing down into the river bottoms. 北佐治亚连绵起伏的山麓地带被犁成了无数弯弯曲曲地垅沟，这样说，对自己那使肥沃的土壤不致被冲洗到河床里去.
...e care of —not even the usual customary book under my arm.破折号后面的是补充说明的意思吗？是不是可以这么理解：he did not take care of even the usual customary book under my arm.
...o times over可以说成over two times吗？ 缘起：柯林斯中over的adv再一次用法例句：
Dave, the pianist, played it over a couple of times.
演奏钢琴的戴夫将这支曲子反复弹了两三遍。
看样子这个over似乎是adv"多余"而不是adv"重复&quo...