go straight down和keep to的区别以及go straight on和go straight ahea

1、go straight down 沿着.一直走（方向是由里向外）
Just go straight down that street.只要沿著那条街一直走.
Go straight down the road and then turn left.沿着这条路一直走,然后左转.
2、keep to 待在；（使）遵守[坚持]；保密；（使）谈话不离题
You've got to keep to the speed limit.你必须遵守限速规定.
He had been unable to keep to his schedule.他没能遵循自己的计划.
Keep to the path or you may lose your way.沿着这条路走,否则你会迷路的.
Keep to the right of the road.请靠右边走.
We always keep to our words.我们一向说话算数.
3、go straight on 继续直走
Go straight on for two miles.一直走两英里.
Go straight on until you come to a large building.一直往前走,直到你走到一座大楼.
Go straight on,take the first turning on the right.一直走,到第一个十字路口向右拐.
4、go straight ahead 一直向前走
Go straight ahead and then turn right.往前直走再向右转.
Go straight ahead ,please ...Look ,these are your rooms .请往前走.——瞧,这里就是你们的房间.
Go straight ahead and turn right at the first corner.向前走,在第一个拐角处向右拐.
go straight on,go straight ahead,还有keep straight on,这三个意思是一样的,没有什么区别.
Keep straight on until you get to the church.一直朝前走就走到教堂了.
Keep straight on till you get to the post office.一直走,不要转弯,到邮局为止.
Keep straight on until you come to a bridge,then turn left.笔直往前走,碰到桥再往左拐.