When first to the market, their products enjoyed great success. A. introducing B

When first ______ to the market, their products enjoyed great success. 　 (2004 全国卷II)

　 A. introducing　 　 B. introduced 　 C. introduce D. being introduced

试题答案

B

their products 与introduce之间构成逻辑上的被动关系，故用过去分词。