Two or more words may be united to form a new one, or to perform the
office of a new one, and four methods or stages of combination may be
noted.
_a._ By _juxtaposition_, where the two words are placed together and yet
remain as distinct words. This method is illustrated in Chinese, where
the words in the combination when taken alone seldom give a clew to
their meaning when placed together.
_b._ By _compounding_, where two words are made into one, in which case
the original elements of the new word remain in an unmodified condition,
as in _house-top_, _rain-bow_, _tell-tale_.
_c._ By _agglutination_, in which case one or more of the elements
entering into combination to form the new word is somewhat changed--the
elements are fused together. Yet this modification is not so great as
to essentially obscure the primitive words, as in _truthful_, where we
easily recognize the original words _truth_ and _full_; and _holiday_,
in which _holy_ and _day_ are recognized.
_d._ By _inflection_. Here one or more of the elements entering into the
compound has been so changed that it can scarcely be recognized. There
is a constant tendency to economy in speech by which words are gradually
shortened as they are spoken by generation after generation. In those
words which are combinations of others there are certain elements that
wear out more rapidly than others. Where some particular word is
combined with many other different words the tendency to modify by wear
this oft-used element is great. This is more especially the case where
the combined word is used in certain categories of combinations, as
where particular words are used to denote tense in the verb; thus, _did_
may be used in combination with a verb to denote past time until it is
worn down to the sound of _d_. The same wear occurs where particular
words are used to form cases in nouns, and a variety of illustrations
might be given. These categories constitute conjugations and
declensions, and for convenience such combinations may be called
paradigmatic. Then the oft-repeated elements of paradigmatic
combinations are apt to become excessively worn and modified, so that
the primitive words or themes to which they are attached seem to be but
slightly changed by the addition. Under these circumstances combination
is called inflection.
As a morphologic process, no well-defined plane of demarkation between
these four methods of combination can be drawn, as one runs into
another; but, in general, words may be said to be juxtaposed when two
words being placed together the combination performs the function of a
new word, while in form the two words remain separate.
Words may be said to be compound when two or more words are combined
to form one, no change being made in either. Words maybe said to be
agglutinated when the elementary words are changed but slightly, _i.e._,
only to the extent that their original forms are not greatly obscured;
and words may be said to be inflected when in the combination the
oft-repeated element or formative part has been so changed that
its origin is obscured. These inflections are used chiefly in the
paradigmatic combinations.
In the preceding statement it has been assumed that there can be
recognized, in these combinations of inflection, a theme or root, as it
is sometimes called, and a formative element. The formative element is
used with a great many different words to define or qualify them; that
is, to indicate mode, tense, number, person, gender, etc., of verbs,
nouns, and other parts of speech.
When in a language juxtaposition is the chief method of combination,
there may also be distinguished two kinds of elements, in some sense
corresponding to themes and formative parts. The theme is a word the
meaning of which is determined by the formative word placed by it; that
is, the theme is a word having many radically different meanings; with
which meaning it is to be understood is determined only by the formative
word, which thus serves as its label. The ways in which the theme words
are thus labeled by the formative word are very curious, but the subject
cannot be entered into here.
When words are combined by compounding, the formative elements cannot
so readily be distinguished from the theme; nor for the purposes under
immediate consideration can compounding be well separated from
agglutination.
When words are combined by agglutination, theme and formative part
usually appear. The formative parts are affixes; and affixes may be
divided into three classes, prefixes, suffixes, and infixes. These
affixes are often called incorporated particles.
In those Indian languages where combination is chiefly by agglutination,
that is, by the use of affixes, _i.e._, incorporated particles, certain
parts of the conjugation of the verb, especially those which denote
gender, number, and person, are effected by the use of article pronouns;
but in those languages where article pronouns are not found the verbs
are inflected to accomplish the same part of their conjugation. Perhaps,
when we come more fully to study the formative elements in these more
highly inflected languages, we may discover in such elements greatly
modified, _i.e._, worn out, incorporated pronouns.