That part isn't strictly wrong, but the whole sentence is awkward in several ways.

For one thing, it has some punctuation problems that in turn create a singular/plural agreement problem. You can't put a comma between the subject and the verb, though you can put one after a sentence adverb, and you should use two commas to set off an interjected phrase.


Furthermore, it shows that language, and with it grammar, is a tool ...
(or even:
Furthermore, it shows that language, and, with it, grammar, is a tool ...)
Furthermore, it shows that language and grammar are tools ...

The end is also sort of a mess. Do you really even need 'to the recipient'? If you must have it, I would put it next to 'convey,' but I think it would be better just to leave it out.

And just logically, isn't grammar a subset of language, not a parallel concept? The idea seems to be something more like 'Language, which of course includes grammar, is ...' -- but you need to clarify that relation in your mind in order to express it clearly.