Be along

through, on, beside, over, or parallel to the length or direction of; from one end to the other of:
to walk along a highway; to run a border along a shelf.
during; in the course of:
somewhere along the way i lost my hat.
in conformity or accordance with:
i plan to revise the article along the lines suggested.
by the length; lengthwise; parallel to or in a line with the length or direction:
he ran along beside me.
with a progressive motion; onward:
the police ordered the line to move along.
(of time) some way on:
along toward evening.
in company; in agreement (usually followed by with):
i’ll go along with you. he planned the project along with his -ssociates.
as a companion; with one:
she took her brother along.
from one person or place to another:
the order was p-ssed along from the general to the captain and from the captain to a private.
at or to an advanced place or state:
work on the new ship is quite far along.
as an accompanying item; on hand:
bring along your umbrella.
along of, chiefly southern u.s. and british dialect.

owing to; because of:
we weren’t invited, along of your rudeness.
in company with:
you come along of me to the store.

get along. get (def 36).
all along, all the time; throughout:
i knew all along that it was a lie.
be along, informal. to arrive at a place; come:
they should be along soon.
preposition
over or for the length of, esp in a more or less horizontal plane: along the road
adverb
continuing over the length of some specified thing
in accompaniment; together with some specified person or people: he says he’d like to come along
forward: the horse trotted along at a steady pace
to a more advanced state: he got the work moving along
along with, accompanying; together with: consider the advantages along with the disadvantages
prep.

old english andlang “entire, continuous; extended; all day long; alongside of,” from and- “opposite, against” (from proto-germanic -andi-, -anda-, from pie -anti “against,” locative singular of -ant- “front, forehead;” see ante) + lang “long” (see long (adj.)). sense extended to “through the whole length of.”
will come, will arrive, as in john said he’d be along in a few minutes, or the doctor’s report will be along by the end of the week. this phrase always indicates a future event. [ ; early 1800s ]

along for the ride
along in years
along the lines of
along with