具体差别在短语中体现。go along是沿着走的意思，比如说顺着某条路走；go down是沿着走下去的意思，有沿着什么走到头的涵义，比如说沿着某条路走到头。go down this street，you can see a post office.
Down副词、形容词、名词、介词、动词，作副词时意为“ 向下；在下面；（坐、躺）下；下降；（数量、力量等）减少；由上至下；向（或在）南方；（写）在纸上；（列）在表格上；（写）在纸上；失去（钱数）；预付；已完成数量（或进度）；到；往楼下；在较不重要之处；离开首都（或重要城市）；从纵向读；由浓变淡；由多到少；由复杂到简单。
短语精讲
1. break down
My car broke down,so I needed to take a bus. （机器等）出故障，抛锚
Her health broke down under the pressure of work. （健康、精神）垮掉
He broke down when he heard the news. 失控痛哭
Talks between the two sides have broken down. （讨论）失败
The two countries met to break down barriers . 砸倒，破除（障碍）
Once buried, the fibers break down. 分解
2. cut down
Half of the forest was cut down to make room for the road. 砍倒
They have to cut down the office staff. 缩减，缩短
3. pull down
The old houses should be pulled down as soon as possible. 拆毁
4. put down
After he finished his exercise,he put down his pen. 放下
Put down your name, please. 写下
Soldiers went in to put down a riot. 镇压
5. take down
Please take down the books from the shelf．取下
We think we took your number down incorrectly. 写下
The machine gun isn&39;t taken down easily. 拆卸，拆掉
6. turn down
Turn down the radio please. 调低（音量或热度）
I thanked him for the offer but turned it down. 拒绝
