1、ETS的辩证法学习得挺好，并在语法上体现得淋漓尽致。所以不要指望用某个通则或公理就来解决问题。一定要具体问题具体分析。(所以从这个意义上说公理是有百害而无一益啊)
好比说ETS喜欢平行结构，对应的它必然给你来一个形式上不平行的正确选项(太多了，举不胜举)。最恶毒的是这个：
396. In recent years cattle breeders have increasingly used crossbreeding, in part that their steers should acquire certain characteristics and partly because crossbreeding is said to provide hybrid vigor.
(A) in part that their steers should acquire certain characteristics
(B) in part for the acquisition of certain characteristics in their steers
(C) partly because of their steers acquiring certain characteristics
(D) partly because certain characteristics should be acquired by their steers(E)
(E) partly to acquire certain characteristics in their steers
另外：
require of sb to do sth
一会儿是对的，一会儿是错的。
cost of... to
也是一会儿是对的，一会儿是错的。
比较的助动词一会儿省略，一会儿不省。
考试时，这根弦一定要绷紧啊!要掌握ETS改错的精髓，并灵活运用。
2、ETS很注重句子的逻辑意思。(好比说比较的对等性和逻辑主语)
很多题目一旦把握了这一点，30秒之内就可搞定。但如果没有把握这一点，就陷入了万劫不复的深渊之中。最有代表性的是这个：
894. Unlike other arachnids, which have their nerve cells evenly distributed along their bodies, the scorpion’s nerve cells are clustered in its head, like a mammal’s.
(A) bodies, the scorpion’s nerve cells are clustered in its head, like a mammal’s
(B) bodies, the scorpion’s head had a cluster of nerve cells, as a mammal does
(C) body, the scorpion has a cluster of nerve cells in its head, as a mammal does
(D) body, nerve cells are clustered in the scorpion’s head, like a mammal’s(C)
(E) body, a cluster of nerve cells is in the scorpion’s head, like a mammal’s
根据可比性，30秒之内肯定可以锁定正确选项就是C。但如果这层纸没有捅破，their body留给我们的选择就只有A或B了吧?
还有很多根据逻辑主语可以锁定一个选项的例子大家自己总结吧。
所以做改错一定首先要明白句子在说什么，说的逻辑意思是否合理。这一点应该摆在第一位，不能就语法来论语法呀。