After Yang Liwei succeeded in circling the earth ,_______our astronauts desire to do is walk in space .
One of the most important problems they had to consider was________of public health.
After the amateur singer competed in the program The Voice of China, his singing career .
Without the development of the Internet, Taobao and Tmall______$ 5.7 billion in sales on 11 November, 2013.
He set out for a remote village for ____ he hoped would be a peaceful retirement.
____ to teaching, as we know, contributes to his popularity with his students.