题目

It was ______ creative thinking that I took the course, not to get high marks in exams. A. developing   B. to develop     C. developed        D. to have developed 答案：B 解析: 略2006年是我国公民义务植树运动开展25周年，25年来我市累计植树154 000 000株，这个数字可以用科学记数法表示为________株．