it is/has been=
it is/has been=
It is/has been + since sb +
it is 时间段和it has been时间 区别
it has been a
It has always been .
It is\has been+时间段+since+一般过去式=时间段+()+since+一般过去式
it is 3 years since Tom has been abroad
Electricity has always been around a__________ it is invisib
It is a week since he has been to BeiJing.
翻译 that is just the way it has always been
It is said _____ has been translated into French.
She has always been busy () it is Sunday.