Our teacher is always busy preparing lessons until 11 o’clock at night, _____we students have gone to sleep.
A.that time | B.by which time | C.by that time | D.which time |
推荐套卷
Our teacher is always busy preparing lessons until 11 o’clock at night, _____we students have gone to sleep.
A.that time | B.by which time | C.by that time | D.which time |