At home, he never seems to have time unt
题型：选择题
问题：
At home, he never seems to have time until after 10?30 pm, ________ his children have gone to bed. [ ]
A. whose time
B. when
C. on which
D. by which time
At home, he never seems to have time until after 10?30 pm, ________ his children have gone to bed. [ ]
A. whose time
B. when
C. on which
D. by which time