A dedicated botanist and _____ Dr. Lian Zhao will lead the expedition to the Amazon next month.
Which choice completes the text so that it conforms to the conventions of Standard English?
For boundary questions, first identify the sentence’s main subject and verb. Then determine whether the material before the blank is a complete clause or an introductory phrase. A colon or semicolon generally requires a complete clause before it, whereas a fronted appositive is followed by a comma that marks where the description ends and the main clause begins.
Hints
Find the subject and verb
Identify who will lead the expedition and locate the verb connected to that subject.
Examine the opening phrase
Consider whether “A dedicated botanist and educator” is a complete sentence or a phrase describing the person named next.
Mark the end of the description
Think about how Standard English marks the boundary between an introductory appositive and the main subject that follows it.
Step-by-step Explanation
Identify the core sentence
The core sentence is “Dr. Lian Zhao will lead the expedition to the Amazon next month.” Here, “Dr. Lian Zhao” is the subject, and “will lead” is the verb.
Identify the opening description
The phrase “A dedicated botanist and educator” describes or renames Dr. Lian Zhao. Because this appositive appears before the main subject, it is a fronted appositive.
Determine the needed boundary
A comma should mark the end of the fronted appositive: “A dedicated botanist and educator, Dr. Lian Zhao will lead the expedition...” Only one comma is needed because “Dr. Lian Zhao” must remain directly connected to its verb, “will lead.”
Eliminate the other punctuation choices
The phrase “A dedicated botanist and educator” is not an independent clause because it has no verb. Therefore, it cannot be followed by a colon or semicolon. Omitting punctuation would also fail to mark the boundary between the introductory appositive and the main subject. Thus, “educator,” is correct.