VOA慢速英语:With Elena Kagan, US Supreme Court Has 3 Women for the First Time

make up组成, 构成

例句：How many countries make up the Common Market?
      (欧洲)共同市场由多少国家组成?

      The audience was made up of very young children.
      观众由小孩子们组成。

2.Politicians and scientists feared that America's technology was falling behind the Soviet Union's. They worked quickly to catch up.

catch up追上, 赶上

例句：You just go ahead and I'll catch up later.
      你先走一步, 我随后赶来。

      You go on ahead; I'll catch you up in a few minutes.
      你继续向前走, 过几分钟我会赶上你的。