we arrived home at 9:00 in the evening,( )most people had al
1个回答

我认为选 B 和 D 都可

by that time 和 by which time 都有 "届时" "之前“ 之意.

另一同义词是 by then.

by xxx 表示事情已经发生了.

that 和 which 是代词,用来显示关系,意思是 这(个),那(个) .

如 the house in which I once lived 我从前住过的房子.

但 by which time 是比较习惯用法.