OG10-39

39. For members of the seventeenth-century Ashanti nation in Africa, animal-hide shields with wooden frames were essential items of military equipment, a method to protect warriors against enemy arrows and spears.

(A)  a method to protect

(B)  as a method protecting

(C)  protecting

(D)  as a protection of

(E)  to protect

      想问问E，OG的解释是Choice E is incomplete; used to protect would have been acceptable.为什么to do不能直接表示equipment的目的呢？

不定式不能单独在句末逗号后面做状语。

起码在GMAT里面没有看到这样正确的例子。

那如果没有逗号，用to protect直接修饰equipment可不可以？

i think that even if there is no comma,to+v  couldn't be used here.

because just in the construction of v ...+ to+v, to+v inducates a perpose.

but here be ..+to+v indicates that someone plan to do somothing or something will happen

1) , to do 永远错！（mahhatan GMAT的人说"We can't use an infinitive after the comma. Remember that an infinitive functions as a verb, but we're trying to introduce a modifying clause here to provide further information about the military equipment.”）

2） 就算这里去掉逗号，前面名词太多， 哪个才是to do 的逻辑主语呢？

3） 好像又看到nn说， 如果是 used to protect 就可以。 相当于 used 短语修饰前面的items,  to do 是 used的固定搭配。

说错了请大家指教。