请教三道SAT语法真题的解答和分析?（2009年5月）谢过.好加悬赏1)A great gray owl flying low across a forest clearing, its wings beating quietly and its ultrasensitive ears tuned to the faint sounds made by small creatures conceal

请教三道SAT语法真题的解答和分析?（2009年5月）谢过.好加悬赏1)A great gray owl flying low across a forest clearing, its wings beating quietly and its ultrasensitive ears tuned to the faint sounds made by small creatures conceal
请教三道SAT语法真题的解答和分析?（2009年5月）谢过.好加悬赏
1)A great gray owl flying low across a forest clearing, its wings beating quietly and its ultrasensitive ears tuned to the faint sounds made by small creatures concealed under leaves.
我知道答案是A要改成Flying lowly.但是,为什么B wings beating不应该改成beat和后面的tuned对应吗?
2)Determined to make a name for herself as a writer of short stories, Helen never submits anything to an editor until revising it several times.
Revising 错在哪?要改成having revised吗?
3)The Roman Poet Virgil is highly esteemed today for his epic poem, The Aeneid, yet on his death bed he himself sought to prevent its publication on the grounds of not being sufficiently polished.
有人说考的是prevent from的固定搭配,但是on the grounds of 这种用法没有错吧?那么应该怎么改?

请教三道SAT语法真题的解答和分析?（2009年5月）谢过.好加悬赏1)A great gray owl flying low across a forest clearing, its wings beating quietly and its ultrasensitive ears tuned to the faint sounds made by small creatures conceal
第一题中的its wings beating quietly and its ultrasentitive ears 是做主语的.beating quietly 是修饰its wings .
整个句子的动词是turned.

2）是的
3 这句话是怎么个意群 prevent ([its publication] on the grounds )of not being sufficiently
prevent...from 然后on the grounds是修饰publication的。on the grounds of是没问题，但是你意群分错了。
1不清楚= =

1 a应该是flows low，助于部分
2 having it revised
3 on the grounds of it not ...