<p>Although praire dogs were once on the verge of extinction, their numbers HAVE RISEN to pre-twentieth century levels because of the work of the environmentalists who LOBBIED for their salvation.</p>
<p>The sentence is correct by the way :)</p>
<p>My question is how can the present perfect be used if there is a sequence of past tense: pre-twentieth century and lobbied.</p>
<p>Is the sentence implying that the environmentalists HAD LOBBIED first, and the numbers of dogs were rising and still rising today.</p>
<p>The numbers are not still rising; they “have risen” already, thanks to the environmentalists’ past lobbying. “Pre-twentieth century” is an adjective phrase that has nothing to do with verb tense, so you can disregard it.</p>
<p>Are you a native English speaker? If so, I think you’re over-thinking this. The sentence flows naturally and sounds correct–so trust your ear!</p>
<p>Thanx, I am definitely overthinking this, but for any sentence you can have a present perfect(Have risen) with a past tense(lobbied.) How is that right though? Shouldn’t it be had lobbied, or is the past perfect implied?</p>
<p>Tense tells when actions have occurred and gives an idea of their period of duration. Tense varies according to the action to which it refers. If a sentence mentions several actions which occurred at different times and had different periods of duration, then the verbs used will reflect those differences by different tense forms. The fact that one action takes a particular tense form does not mean that all other actions mentioned in the same sentence require a similar form.</p>
<p>While wood5440 is right in his description of tenses and how they are chosen, the point in the SAT writing is to determine whether there are errors in the question text. But if the time context in the text is ambiguous then the question is problematic.</p>
<p>My sense is that their isn’t sufficient clarity in the text to determine the right tense for “lobbied”. If this weren’t a SAT question then we would take the tense at face value – sometime in the past environmentalist “lobbied” for legislation. We don’t know if the increase in population started when this lobbying began, or sometimes after. We don’t know whether this lobbying ended. It simply was something that happened.</p>
<p>So if “lobbied” was NOT marked as a possible error, there is no discussion regarding its correctness. But it is picked as an error candidate, and this is unfortunate.</p>
<p>There are other possible choices: “have lobbied” and “had lobbied”. The sentence implies a timeline and an argument can be made for either of these choices.</p>
<p>I think that this is a poor question, and not worth a great deal of analysis.</p>