____the problem of land erosion(侵蚀) getting more serious, the government is searching for a way to deal with it. 

What my teacher said about planning for the future set me______.

--- What are you going to do next?--- To write a science story about outer space ___ by Science and Technology Press.

_____ in bed, we listened to the heavy rain _______ the window.

When I came in, I saw her sitting in the sofa ______ in thought.