SAT grammar question:
(It appears) that natural rubber was first processed (by) the ancient Mayan people, (using) it to make sandals, figurines, and even some rundimentary sports equipment. (No error)
The parentheses designate areas where the grammar of the sentence may be incorrect. You have to select the area which is in error (or select “No error” if there is no error in the sentence).
(using) is the error in the sentence.
Can someone explain why (using) is incorrect?
This is a really tricky question. To my native (AmE) ear, you should definitely say “who used it”:
It appears that natural rubber was first processed by the ancient Mayan people, who used it to make sandals …
But why? It’s not that the verb needs to be in the past tense. If you switch the sentence around to make it active, you get a sentence that sounds fine:
It appears that the ancient Mayan people processed natural rubber first, using it to make sandals …
And it’s not that continuous-verb subordinate clauses always have to have the same subject as the rest of the sentence. Consider the sentence:
Yesterday I met Sally, walking her dog.
This has the same grammatical structure as the incorrect SAT sentence, but it sounds fine to me.
I think the rule is that if the continuous-verb subordinate clause does not have the same subject as the rest of the sentence, you need to be able to add the elided who and the elided verb. Trying this in the two cases, we get
*It appears that natural rubber was first processed by the ancient Mayan people, who were using it to make sandals …
Yesterday I met Sally, who was walking her dog.
In the first sentence (indicated by *), the continuous tense is incorrect. In the second, it’s fine.