Which translation best preserves the meaning of '他去年完成了研究'?
答案解析
**Core Concept:** Tense accuracy in translation
**Analysis:** The Chinese sentence clearly indicates a completed past action.
**Correct Answer:** C. Simple Past correctly expresses completed action with specific time marker.
**Error Analysis:**
- A: Present tense mismatch
- B: Present Perfect conflicts with specific time
- D: Past Continuous suggests ongoing action
**Common Mistake:** Incorrectly using Present Perfect with time-specific references.
正确答案:C