as far as
To the degree or extent that: They returned at nine, as far as we know.
Usage Problem Concerning; regarding.Usage Note: As far as has recently been used as a preposition meaning “as for” or “regarding,” especially in speech. This construction derives from the term's use as a conjunction (as in as far as the election goes), but with the verb of the clause omitted (as far as the election). A large majority of the Usage Panel frowns upon this usage. In our 1994 survey, 80 percent found the prepositional use unacceptable in this example: As far as something to do on the weekend, we didn't even have miniature golf. Fully 89 percent objected to as far as when followed by a noun clause in As far as how Koresh got shot, we don't know yet.Our Living Language Despite the admonitions detailed in the Usage Note, it is the case that many speakers often drop the verbal part of the as far as construction, as in As far as a better house, I don't want one (instead of As far as a better house is concerned &ellipsis;). This trend is more noticeable in speech than in writing. Like other examples of language variation and change, a number of constraints that we follow regularly, although unconsciously, govern the dropping of the verb in as far as constructions. For instance, if as far as precedes a personal pronoun or one whose point of view is being represented (as far as he is concerned), the verb cannot be deleted (notice that as far as he is strikingly ungrammatical). The longer and more complex the noun or sentence that follows as far as, the more likely the verb is to be omitted. Thus, As far as getting a better house to live in, we &ellipsis; is more likely to be uttered than As far as a house, we&ellipsis4; The very similar phrase so far as is found within verbless constructions in complex sentences that use gerunds as early as the 19th century, as in Jane Austen's novel Emma: “So far as our living with Mr. Churchill at Enscombe, it is settled.” These omissions in longer constructions seem to have initiated the change leading to their omission in short locutions. Only in the 20th century do we find first noun phrases and then simple nouns without a form of go or be concerned.
as far as