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Do I use 'is' or 'are' in this sentence?
I have been looking at subject-verb agreements and I need some clarification on this sentence:
”...research of neotropical species and their declines is/are a prominent topic.”
The thing that throws me off is the word species. It is used both as a plural and a singular (but plural here). This seems to fit with Rule #10 on the OWL Purdue site (http://owl.english.purdue.edu/owl/resource/599/01). Any biology writers out there?
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