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

We left the small town, _      clearly _       no need to stay．

Montreal is the second largest French-speaking city in the world, Paris _____ the largest. 

        with a difficult situation, I decided to ask my parents for advice.

It was a pity that the great writer died _______his works unfinished.