BeckyRobinsonTPR wrote:
Official Answer:
There are two main issues in this sentence, pronoun and verb tense. I will choose to work with verb tense as the first issue. In this case, one thing happened before another in the past and therefore the first event requires the use of past perfect while the second event requires simple past. There are some cases, in which specific time is mentioned in which past perfect is optional but this is not such a case because the event happened at an undetermined time in the past.
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