When flint to the market, these products enjoyed great success. A. introducing B

When flint _______  to the market, these products enjoyed great success.

   A. introducing             B. introduced

   C. introduce                D. being introduced

试题答案

B

解析：．

根据题干提示，此题省略了主语和be动词，补全后应为When these products are

first introduced to the market，因products与introduce之间构成动宾关系，所以应用过去分词形式，所以正确答案为B。