Prepositions(最佳解答者have 40分)

Adpositions form a heterogeneous class, with fuzzy boundaries that tend to overlap with other categories (like verbs, nouns, and adjectives). It is thus impossible to provide an absolute definition that picks out all and only the adpositions in every language. The following properties are, however, characteristic of the most frequently used, "core" members of most adpositional systems:

Adpositions are among the most frequently occurring words in languages that have them. For example, one frequency ranking for English word forms [1] begins as follows (adpositions in bold):
the, of, and, to, a, in, that, it, is, was, I, for, on, you, …
The most common adpositions are single, monomorphemic words. According to the ranking cited above, for example, the most common English prepositions are:
of, to, in, for, on, with, as, by, at, from, …
An adposition combines syntactically with exactly one complement phrase, most often a noun phrase.
An adposition establishes the grammatical relationship that links its complement phrase to another word or phrase in the context.
An adposition determines certain grammatical properties of its complement (e.g. its case).
Adpositions are non-inflecting (or "invariant"); i.e., they do not have paradigms of forms (for different tenses, cases, genders, etc.) in the same way as verbs, adjectives, and nouns in the same language.
Adpositions form a closed class of lexical items and cannot be productively derived from words of other categories.
Simple adpositions consist of a single word, while complex adpositions consist of a group of words that act as one unit. Some examples of complex prepositions in English are:

in spite of, with respect to, except for, by dint of, next to
The boundary between simple and complex adpositions is not clear-cut. Many simple adpositions are derived from complex forms (e.g. with + in → within, by + side → beside) through grammaticalization. This change takes time, and during the transitional stages the adposition acts in some ways like a single word, and in other ways like a multi-word unit. For example, current German orthographic conventions recognize the indeterminate status of the following adpositions, allowing two spellings: [2]

anstelle / an Stelle ("instead of"), aufgrund / auf Grund ("because of"), mithilfe / mit Hilfe ("thanks to"), zugunsten / zu Gunsten ("in favor of"), zuungunsten / zu Ungunsten ("to the disadvantage of"), zulasten / zu Lasten ("at the expense of")
The boundary between complex adpositions and free combinations of words is also a fuzzy one. For English, this involves structures of the form "preposition + (article) + noun + preposition". The following characteristics are good indications that a given combination is "frozen" enough to be considered a complex preposition in English:

The surface position of an adposition with respect to its complement allows us to define the following subclasses:

A preposition precedes its complement to form a prepositional phrase.
German: auf dem Tisch, French: sur la table, Polish: na stole ("on the table")
A postposition follows its complement to form a postpositional phrase.
Mandarin: zhuō shàng, Japanese: teeburu ni (lit. "table on")
These two terms are in fact much more commonly used than the more general adposition. Whether a language has primarily prepositions or postpositions is seen as an important aspect of its typological classification, correlated with many other properties of the language according to research into linguistic universals.

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