The も particle has the meaning of
also
too
words of similar weight
about (emphasizing an upper limit)
as much as
even
more
further
other
again
So depending where it's placed like before/after a subject/verb/adj/noun etc.
Can you determine based on that what meaning it has ?
To some extent you can, but Japanese is a heavily context based language and it is context that is key to determining the appropriate translation of も.
Consider
今日{きょう}は車{くるま}が10台{だい}も売{う}れた。
I sold as many as ten cars today.
I don't think there's any ambiguity there since も comes after a counter. But what about
今日{きょう}は車{くるま}も売{う}れた。
It could be
(I finally manged to sell the motorbike and) I even sold the car today.
or
( I sold the motorbike and) I also sold the car.
The more I think about it the more I find that these definitions of も merge into each other, even in English (in Japanese and also in English).
も is a very versatile and often quite confusing particle. You should post specific example sentences where you are having problems working out which meaning to use.
