go down a main street和go along the main steet的区别.

问题描述:

go down a main street和go along the main steet的区别.
set off down a main street.沿着主街道出发.这里down 是沿着的意思?那和long 有什么区别?

就和我们通俗说法一样,这条路走下去,走下去也可以当作一直往前走
即go down the street 和go along the street