one of my monikers in cyberspace, unsumupable, has stirred up an interesting controversy lately. a particular friend approves of it heartily, but comments, "shouldn't it be 'unsumableup'?" how can one be 'right' when making up a new word? how can we possibly decide? of course, linguistics might offer a solution...
so, what's going on here? we have ourselves a verb, "to sum" or maybe "to sum up," and a couple of affixes, "un-" and "-able," which make it into an adjective. our dispute is over whether "-able" should attach to "sum up" as though it were a single verb or just to "sum," with "up" acting as a modifier.
i'm not considering renaming myself--i've been unsumupable too long and it's got a much nicer rhythm than unsumableup. but the question brings up a point that concerns a whole slew of verbs. some of these are discussed in this older Invented Usage post. a lot of verbs take following prepositions that seem to drastically change their meaning. "come up with" is definitely different than "come with," for example. and "to break in" is different than "to break."
in some cases, a noun can go between the verb and preposition, as in "i broke the baseball glove in." though it also seems acceptable to say "i broke in the baseball glove."
it's also very clear that some suffixes do belong on the first half of these verb-preposition pairs. the past tense, for instance, is clearly 'summed up,' not 'sum upped' and we definitely say 'summing up' not 'sum upping.' i'm trying to think of other suffixes to test my intuition about where the would attach, but they all involve creating a new word that's subject to my friend's skepticism. i would say 'sumupper' for someone who sums things up, but he's argued for 'summer up.' the 'correctness' of these forms comes down to the intuitions of native speakers, and in this case speakers disagree! (we also noted that someone spontaneously generated the form 'breakable in'... -1 for me.)
another friend commented on that post cited above that maybe these prepositions might not be completely separate entities, but might function as part of the verb itself. they may act as separable affixes (which exist in other languages like German) that go after some suffixes and before others.
linguists identify two classes of affixes: derivational and inflectional. derivational affixes change the part of speech of a word. -able, for instance, changes a word from a verb to an adjective. inflectional affixes do not change the part of speech and include more grammatical markers such as the plural -s and the past tense -ed. for the purposes of this post, it's also very important to note that derivational suffixes always attach closer to the root of the word than inflectional suffixes do. for instance, from institute we can derive institution (-tion), institutional (-al) and institutionalize (-ize), and then inflect it as institutionalizes or institutionalized. the -s or -ed would never occur closer to the root than intervening derivational suffixes.
so if prepositions in these verbs act as suffixes, we should be able to categorize them as derivational or inflectional and then determine where -able should go in relation to them. prepostions do not change the part of speech of the verb, a feature they share with inflectional affixes. but they seem to have a larger impact on the meaning of the word than most inflections--they have a semantic, rather than a grammatical function, much like derivational affixes.
some examples that almost stumped my skeptic friend were the suffixes "-mania" and "-nik" (as in beatnik, one who is zealous about the affixed verb to the point of silliness). i like "sumupnik" and "sumupmania" and i don't think anyone could defend "sumnik up" or "sumania up." he was tempted, however, to say "upsumnik" and "upsumania," which i find surprisingly reasonable. this also seems to support the theory that these prepositions are somewhat like the separable german prefixes and are represented as prefixes in some way. we can even find some 'real' examples like "off-putting" as the adjective of "to put off." at the very least, i think our analysis should clearly include a notion of unity--some forms seem to require the verb and preposition to act as a unit, no matter how you unite them.
so maybe it's even more complicated than we previously thought! maybe we treat the verb and preposition as a unit in cases where we're turning it into a noun, separately when we're adding inflections and we can disagree about whether they're a unit or not when we're making them into an adjective. this kind of thing drives syntacticians nuts... to derive rules, they have to first agree on what seems right to them as native speakers. they often go "sumupnik, upsumnik, sumupnik, upsumnik. which sounds right to me?" i, for one, don't trust my intuition that much.
my guess is that when we decide to make a compound we've never heard before, we search for a familiar template to use when constructing it so that others will quickly understand the relationship we're trying to express between the parts. how do we decide which verbs should go in the same template? some possibilities: semantic or syntactic similarity--we look for the verb that takes the most similar objects and indirect objects and gives them the most similar relationship to the one we're trying to express; prosody--we think of a familiar rhythmic template that closely matches the new verb; frequency--we use whatever pattern occurs in the most verbs that we know and use often. or maybe it's some mixture of various methods. once a form has been used enough, though, it doesn't matter how it got started. it becomes convention--arbitrary and good enough, like all language.
usage, as always, offers another solution: a google search for "unsumupable" returns 38 hits (only the first four relate to me), while "unsumuableup" returns zero. draw your own conclusions.