选出下列各题的答案,并说明理由1、Early____the morning of May lst,we started

选出下列各题的答案,并说明理由
1、Early____the morning of May lst,we started off____the mountain village.
A.in;for B.in;to C.on;/ D.on;for
2、The population of the world has grown very fast_______four hundred years.
A.for the past B.in the pass C.in the past D.for past
3、The shop____elothes is_____the right side_____the street.
A.of;at;beside B.for;on;at C.for;in;of D.of;in;of