When            to someone,I usually say, "Pleased to meet you."

introduce

introduced

introducing

am introduced

考查过去分词和省略。句意：当我被介绍给别人时，我通常会说：“很高兴认识你”。根据句子结构可知，本句是when引导的时间状语从句，原句when I am introduced to someone,这里当从句主语与主句主语一致时，并且从句的谓语动词有be这时从句的主语与be同时省略，所以空格处introduced。故选B项。

They elected him          captain of the team for         second time.

the; a

a; the

a; a

/; a

考查冠词的用法。句意：他们再次选他当队长。职位，官衔前面不加冠词，a second time表示“又一次，再次”；the second time表示第二次（顺序）。故选D项。

While we may not be born with a nature talent, we can          for it with hard work.

break up

take up

bring up

make up

考查动词短语辨析。句意：虽然我们可能没有与生俱来的天赋，但我们可以通过努力工作来弥补。A. break up打碎；B.take up 拿起，开始从事；C.bring up提出；D. make up 弥补。根据上文we may not be born with a nature talent可知没有与生俱来的天赋，所以要通过努力工作来弥补。故选D项。