listen to the material carefully,although it is difficult and sometime you can't write down the correct answer.As long as you have tried,whatever you write down will be the harvest of yours.You should believe that only by accumulating little by little could you learn English welll.so come on.
In 1929,three years after his flight over the North Pole, the American explorer, R.E.Byrd,successfully flew over the South Pole for the first time. Though, at first, (1)_______________________. At one point, it seemed certain that their plane would crash. (2)________________________.Byrd at once ordered his men to throw out two heavy food sacks. The plane was then able to rise and it cleared the mountains by 400 feet. (3)______________________. The aircraft was able to fly over the endless white plains without difficulty.