Madame Curie(居里夫人) contributed all his life ______ radium(镭) so that she has earned respect from people all over the world.

Who’s the girl with brown hair— is Maria.

_______ excited his parents most is that he had passedthe entrance exam and was admitted into his dream college

Do you know in ancient China— I have no idea. But I know people once used tree leaves to make paper.

_______ of the students will take part in the sports meeting.