If you really have to leave during the meeting, you'd better leave （ ） the back door.
（A）for
（B）by
（C）across
（D）out
There were a lot of visitors from Japan （ ） the foot of the mountain.
（A）on
（B）at
（C）in
（D）to
He usually gets to school （ ） bike （ ） school days, but he sometimes gets to school by bus.
（A）on; by
（B）on; on
（C）by; on
（D）by; by
