In The structure of English (New York, 1952), Charles C. Fries describes a small group of intensifiers, which he labels Group D and identifies as words that pattern like very. The group is established (92) with the following frame: The (A) concert (1) may (B) not (C) be (2) very (D) good (3) then (4). Substituting in this frame, he gets, as members of Group D, very, quite, really, real, pretty, fairly, rather, awfully, awful, any, too, more, most. We are not told that these are the only members in the corpus examined by Fries; but the implication is that if the group extends beyond this list, it doesn't extend far.