"The indispensable basis of all is knowledge of the language, the mother tongue and the tongue of the Torah. From an early age every child in Israel should become familiar concurrently with the language of his country and with that of the writings which are to guide his life, -namely, Hebrew. In and from these writings he should derive his understanding of things and their relations, from them his ideas should be illustrated and clarified, from an early age his spiritual life should be developed by them. Anyone who realizes how a man's whole way of thinking takes its stamp and colouring from the language in which he speaks and thinks will agree with our Sages in regarding it as a matter of some consequence that the child should learn the holy language of the Scripture at an early age.' With it you place in his hands the key to realizing that the Scriptures ought to be the basis and source of his life, and also to making them actually his constant companions in life. Begin, therefore, with the language, and let him first read the Torah more with a view to enriching his knowledge of the language."
Rabbi Samson Raphael Hirsch, Horeb 551
Does this necessarily mean grammar and conversation? I know numerous American yeshiva bochurim who are not comfortable with Hebrew. They can manage some of the Rambam, which is easier Hebrew, and some Gemara Rashi, but there are all kinds of books that they cannot read. This after twenty years in school! A neighbor of mine tested some boys in a local mesivta in America and found that they could not read simple Hebrew text. And by read I mean understand, translate. The Orthodox Jewish world is the only society I know of that defines reading as saying words without understanding them. Anywhere else that is called illiteracy.
We are a people that describes itself as being built around scholarship. One day a week we don't allow children to play with balls because we want them to study instead - all day. We don't build ball fields in Charedi neighborhoods because we want the children to study. We pray two hours a day in Hebrew. How many Jews can read that Hebrew? I know numerous cheder children that pray without understanding a word! What is prayer if you don't understand the words? We must teach grammar. I go to shiur after shiur that consists of the maggid shiur racing through a sentence of Hebrew and translating. One does not learn Hebrew that way. The brain turns on for the English, shuts off for the Hebrew, probably not grasping much in either tongue. It's like listening to a message coming through a bad short wave radio connection. I heard an interview with a graduate of the Realschule in Frankfurt where he talked about how the children there studied grammar. And here in Horeb, Rav Hirsch clearly calls for formal language instruction as the first of seven categories of a plan for education:
We may therefore tabulate the general subjects of instruction for Jewish youth as follows:
(I) Hebrew language.
Concurrently and as living languages at an early age along with general knowledge and development of the mind.
(3) Torah, Nevi'im and Kethuvim.....
Rabbi Samson Raphael Hirsch, Horeb 552
He doesn't say to study Chumash with a translation. He says to study Hebrew language. It comes before Tanach! Why? Because you can't read a Hebrew text without knowing Hebrew well. And to know it well you must study it as a language, by itself so that it becomes a living language, which means a language one can speak. And as we know Rav Hirsch was not a Zionist. So he is not recommending Hebrew language proficiency so that one can make aliyah, something that did not exist in his day. He demands language study so that one can study Torah.
The Maharal also promoted study of grammar.