【简答题】听下面一段材料,回答1-4题。 1. How many American rivers are seriously polluted? A. One-sixth of them. B. One-third of them. C. Half of them. 2. When did Susan start the work of cleaning the river? A. Three years ...
【单选题】?Read the article below about 'China Enters Cyberspace' and the questions. ?For each question 13~18, mark one letter (A, B, C or D) on your Answer Sheet for the answer you choose. China Enters Cybersp...