It ___(be)one and a half years since I __(begin) to study English.

问题描述:

It ___(be)one and a half years since I __(begin) to study English.

is have begun

has been begun

has been began
全句翻译:自从我开始学习英语到现在已经一年半了。
前半句用现在完成是,表示持续到现在的状态;
后半句用过去时,表示过去的时间发生的事

has been begin

has been
began