on the street和down the street用法

ON the street ：指在这条街的路面上
无门牌号前street用in或on，如：in Baker Street/ in the High Street（英国用法）；on Larrie Street/ on Upper Beamish Street （美国用法）。

walk down the street--沿街行走。

(1) On the street = 美国: 在街上: He was standing on the street when the car exploded.

(2) In the street = 英国: 在街上 : He was walking in the street when the I saw him.

(3) Down the street = 沿着,顺着街道= (a) He walked down the street this morning.
(b) If I'm just walking down a street, can a Police Office grab me and search me for no reason?