有两种用法,第一种是做介词,还有一种是副词的
一、作介词时,along意为“沿着”：
1.Many trees were planted along the river-bank.沿着河岸种植了许多树.
2.The Chinese people are pressing ahead along the socialist road.中国人民正沿着社会主义道路奋勇前进.
3.There are trees all along the road.沿着这条路从头到尾都有树.
二、作副词时along意为“向前”,常与动词或介词with连用,构成一些常用词组.例如：
1.Let us walk along.让我们向前步行.
2.she will send it back along with some other things.她将此物与其他东西一并送回.
3.The mechanization of agriculture will raise to the output,and,along with it,the living standard of the peasants.农业机械化将提高产量,同时也将提高农民的生活水平.
4.He gets along very well with us.他和我们相处很好.
5.How are you getting along?
6.How is she getting along with her work?她工作进展如何?
7.I knew that all along.对那件事我一开始就知道.