"along" 是一个介词和副词，其用法如下：

作为介词 ，"along" 后面通常接宾语，表示沿着某物或某方向移动或存在。例如：

She walked along the beach.

They came along just as we were starting the meeting.

作为副词 ，"along" 可以表示向前或一起，常用于运动动词之后，也可以用于描述伴随的情况。例如：

The train pulled along slowly.

They talked along while walking to the park.

固定短语搭配 中，"along with" 表示“和…一起”，用于连接两个并列的成分。例如：

She came along with her sister.

They went along with the plan.

根据这些用法，"along" 后面可以接宾语或用于固定短语搭配。具体接什么取决于句子的语境和所要表达的意义。