Question

英语单选题by the end of this

一道英语选择题 By the end of this year, it ____________ 16 years since the emergence of the World Wide Web as an electronic–publishing vehicle.
A) has been C) will be B) will have been D) had been
希望能解释下道理 这句话 怎么翻译呢

Answer 1

1. 答案：B will have been.
2. 翻译：到今年年底时,互联网作为一种电子出版工具,面世已经16年了.
3. 解释：
1）前面有by the end of,后面又有since引导的时间状语从句,主句必须采用完成时；
2）从句意来看,今年年底是将来的时间,所以主句又必须有将来的时态；
3）上述两者结合即将来完成时：will have + 动词过去分词
它表明到将来某个时间为止所完成或延续的动作或状态.
再如：I'll have been 30 years old by the end of this year.
到今年年底时,我会有30岁了.