题干

.
The symbolic one-hour switch-off first _____ in Sydney in 2007 has become an annual global event.

A:to hold

B:being held

C:to be held

D:held

上一题 下一题 0.0难度 选择题 更新时间:2018-09-23 03:32:21

答案(点此获取答案解析)

D