Prefixes. But words may be formed by prefixing syllables, or by combining two or more words into one. Many of these formations were effected in the Latin before the words were introduced into English; but we can study the principles governing them and gain a key to the spelling of many English words.
In English we unite a preposition with a verb by placing it after the verb and treating it as an adverb. Thus we have “breaking in,” “running over,” etc. In Latin the preposition in such cases was prefixed to the word; and there were particles used as prefixes which were never used as prepositions. We should become familiar with the principal Latin prefixes and always take them into account in the spelling of English words. The principal Latin prefixes are:
ab (abs)——from ad——to ante——before bi (bis)——twice circum (circu)——around con——with contra (counter)——against de——down, from dis——apart, not ex——out of, away from extra——beyond in——in, into, on; also not (another word) inter——between non——not ob——in front of, in the way of per——through post——after pre——before pro——for, forth re——back or again retro——backward se——aside semi——half sub——under super——above, over trans——over, beyond ultra——beyond vice——instead of.
Of these prefixes, those ending in a single consonant are likely to change that consonant for euphony to the consonant beginning the word to which the prefix is attached. Thus ad drops the d in ascend, becomes ac in accord, af in affiliate, an in annex, ap in appropriate, at in attend; con becomes com in commotion, also in compunction and compress, cor in correspond, col in collect, co in co-equal; dis becomes dif in differ; ex becomes e in eject, ec in eccentric, ef in effect; in becomes il in illuminate, im in import, ir in irreconcilable; ob becomes op in oppress, oc in occasion, of in offend; and sub becomes suc in succeed, sup in support, suf in suffix, sug in suggest, sus in sustain. The final consonant is changed to a consonant that can be easily pronounced before the consonant with which the following syllable begins. Following the rule that the root must be changed as little as possible, it is always the prefix, not the root, which is compelled to yield to the demands of euphony.
A little reflection upon the derivation of words will thus often give us a key to the spelling. For instance, suppose we are in doubt whether irredeemable has two r's or only one: we now that redeem is a root, and therefore the ir must be a prefix, and the two r's are accounted for,—indeed are necessary in order to prevent our losing sight of the derivation and meaning of the word. In the same way, we can never be in doubt as to the two m's in commotion, commencement, etc.
We have already noted the tendency of y to become i in the middle of a word. The exceptional cases are chiefly derivatives from the Greek, and a study of the Greek prefixes will often give us a hint in regard to the spelling of words containing y. These prefixes, given here in full for convenience, are:
a (an)——without, not amphi——both, around ana——up, back, through anti——against, opposite apo (ap)——from cata——down
dia——through en (em)——in epi (ep)——upon hyper——over, excessive hypo——under meta (met)——beyond, change syn (sy, syl, sym)——with, together
In Greek words also we will find ph with the sound of f. We know that symmetrical, hypophosphite, metaphysics, emphasis, etc., are Greek because of the key we find in the prefix, and we are thus prepared for the y's and ph's. F does not exist in the Greek alphabet (except as ph) and so we shall never find it in words derived from the Greek.
The English prefixes are not so often useful in determining peculiar spelling, but for completeness we give them here: