判断下列句子的正误。假如错误，请改正。
1 How hard did she try!
2 He pointed out that not once had she complained.
3 Not long afterwards, did he move to Bonn.
4 only two of them he found useful.
5 only a few days later, did he move to Bonn.
6 So wet had been the pitch that theyd abandoned play.
谢谢曹老师出题，试答如下，错误之处请曹老师和各位专家指正：
1. How hard did she try!
正确。在 how 和 what 引导的感叹句里可以用倒装语序，但属相当老式的使用方法。
2. He pointed out that not once had she complained.
正确。not once 属表否定意义的副词，用于句首（分句句首），其后用倒装。
3. Not long afterwards, did he move to Bonn.
错误。Not long afterwards 虽然含有 not，但意思上并不表示否定。
改正：Not long afterwards, he moved to Bonn.
4. only two of them he found useful.
正确。only 修饰宾语时若坐落于句首，其后的句子可以倒装也可以不倒装。
5. only a few days later, did he move to Bonn.
错误。only 后面虽然接是状语，但它并不具备排他性，故其后不需要倒装。
改正：only a few days later, he moved to Bonn.
本看法引自陈根花老师的以下文章：
http://www.yygrammar.com/Article/201305/3222.html
6. So wet had been the pitch that theyd abandoned play.
错误。been 不可以提前。
改正：将 been 放在 the pitch 后面。