問題詳情：
A knife attack happened at the subway and at least 3 people ________.
A. killed B. are killed C. were killed D. were killing
【回答】
C
【解析】句意：在地鐵裏發生了一起用*襲擊事件，至少三人被捅死。and是並列連詞，前後動詞時態一致，根據happened可知用過去式，結合句意可知用被動語態。被動語態構成：be+動詞的過去分詞。故選C。
知識點：動詞語態
題型：選擇題
