I learned that e.g. while 「彼は食べていた。」means "He was eating.",「彼はもう食べていた」means "He had already eaten." In that case, does using もう in this context always transform the meaning from a continuous state to a resultant state, or is it ambiguous? That is, what if I want to say "He was already eating?" I guess I can say something like 「彼はもう食べ始まっていた。」 to be unambiguous, but is simply 「彼はもう食べていた。」 still correct?