Definitions of along:

• adverb:   with a forward motion

  Example: "We drove along admiring the view"

• adverb:   in accompaniment or as a companion

  Example: "His little sister came along to the movies"

• adverb:   in addition (usually followed by `with')

  Example: "We sent them food and some clothing went along in the package"

• adverb:   to a more advanced state

  Example: "The work is moving along"

• adverb:   in line with a length or direction (often followed by `by' or `beside')

  Example: "Pass the word along"