____all kinds of difficulties,the workers have made rapid progress in the construction of the World Expo 2010 Shanghai.
Living in the central Australian desert has its problems, _____ obtaining water is not the least.
— Where _____ the recorder? I can't see it anywhere.— I _____ it right here. But now it's gone!
— I didn't tell my parents the secret yesterday. — But you ______.
In 1911, Madame Curie received a second Nobel Prize for her research, the first person in the world ______ two Nobel Prizes.
A 16-year-old male student had been infected with bird flu in Hunan province , the fourth case of human bird flu found in China.