by dmitryknowsbest Fri Dec 24, 2010 1:33 am
Since the main subject-verb pair here is "Owen walked," the sentence is still in the active voice. The word "head" is the object of the verb "held," which technicallty has no identified subject (although we can figure that it is Owen, not someone else, who is holding his head high!).
However, we could also start the sentence with "Holding his head high." It's really just a stylistic difference.
Also, remember that the active/passive distinction is a preference, not a rule. There are many cases in which the passive voice is actually more appropriate than the active. This is certainly the case when the noun in question cannot be an active subject ("Corn has been used as a food crop by many civilizations.")
We might also use the passive voice to emphasize the most important element: "The king was murdered" or "My car was stolen." In such cases, the fate of the king or the car is more important to us than the person acting (and we may not even know who did these things), so we use the passive. Otherwise, we would have to say "Someone murdered the king," or "Someone stole my car." Both of these are grammatically correct, but they don't have the same impact.
Dmitry Farber
Manhattan GMAT Instructor