单项选择题A．20 billion dollarsB．80 billion dollarsC．100 billion dollarsD．120 billion dollars

单项选择题A．the Works Manager has made a mistakeB．Holder and Bragg has acted dishonestlyC．the Purchasing Manager has made a mistakeD．more spare parts than needed have been used

填空题将politics改为political。

填空题factors forms

填空题将being改为been。