.______ his homework, he went on to preview the next lesson.
The financial crisis has put the world economy in a difficult _________.
The collapse of the World Trade Centre has put US economy in a difficult ___________.
More and more people choose to shop in a supermarket as it offers a great _______of goods.
Life is tough in the city. In order to lose their_______,some people drink alcohol.
One of the consequences of our planet's being warming up is a(n)_______ in the number of natural disasters.