问题
选择题
The machine has been used many years. It’s no wonder that it doesn’t work well________.
A．regularly
B．constantly
C．occasionally
D．frequently
答案
答案：C
题目分析：A. regularly定期地，B. constantly 连续地，不断地，C. occasionally偶尔地，D. frequently经常地，句意：这个机器已经被使用了很多年，难怪它偶尔不工作了。所以选C。