一直觉得很奇怪。动名词在句子当中当作名词使用，为什么不能和名词平行呢？
印象中有做过这样的题。就是正确答案中的结构是……and……的。然后是一个动名词和名词平行的，但是现在怎么都找不到这个题目了。
在prep1 中52 的B就是因为动名词和名词不能平行所以选项错了。
52. (27251-!-item-!-188;#058&003145)
In addition to her work on the Miocene hominid fossil record, Mary Leakey contributed to
archaeology with her discovery of the earliest direct evidence of hominid activity and painstakingly
documenting East African cave paintings.
(A) Leakey contributed to archaeology with her discovery of the earliest direct evidence of hominid
activity and painstakingly documenting
(B) Leakey contributed to archaeology by her discovery of the earliest direct evidence of hominid
activity and by painstakingly documenting
(C) Leakey was a contributor to archaeology with her discovery of the earliest direct evidence of
hominid activity and with her painstaking documentation of
(D) Leakey's contributions to archaeology include her discovery of the earliest direct evidence of
hominid activity and her painstaking documentation of
(E) Leakey's contributions to archaeology include discovering the earliest direct evidence of
hominid activity and painstaking documentation of
考点: 平行对称（Parallelism）
1) and, but等连词出现的时候,一定要注意前后平行
(A) and前后不平行,前者是名词discovery,后者是动名词documenting；with用于此处意思不准确。
(B) and前后不平行,名词discovery和动名词documenting不平行
(C) 使用contributor改变了原句的意思,with意思太广泛,不如include表达意思精确
(D) 正确, and前后平行都是名词discovery, documentation
(E) and前后不平行,前者是动名词discovering,后者是名词documentation | 
