The following is an excerpt from wikipedia, Classical Chinese Grammar:
Grammar
Further information: Classical Chinese lexicon
Classical Chinese is distinguished from written vernacular Chinese in
its style, which appears extremely concise and compact to modern
Chinese speakers, and to some extent in the use of different lexical
items (vocabulary).[citation needed] An essay in Classical Chinese,
for example, might use half as many Chinese characters as in
vernacular Chinese to relate the same content.
In terms of conciseness and compactness, Classical Chinese rarely uses
words composed of two Chinese characters; nearly all words are of one
syllable only. This stands directly in contrast with modern Chinese
dialects, in which two-syllable words are extremely common. This
phenomenon exists, in part, because polysyllabic words evolved in
Chinese to disambiguate homophones that result from sound changes.
Similarly, Chinese has acquired many polysyllabic words in order to
disambiguate monosyllabic words that sounded different in earlier
forms of Chinese but identical in one region or another during later
periods. Because Classical Chinese is based on the literary examples
of ancient Chinese literature, it has almost none of the two-syllable
words present in modern Chinese languages.
Pronouns
Classical Chinese has more pronouns compared to the modern vernacular.
In particular, whereas Mandarin has one general character to refer to
the first-person pronoun ("I"/"me"), Literary Chinese has several,
many of which are used as part of honorific language (see Chinese
honorifics), and several of which have different grammatical uses
(first-person collective, first-person possessive, etc.).[citation
needed]
Syntax
In syntax, Classical Chinese is always ready to drop subjects, verbs,
objects, etc. when their meaning is understood (pragmatically
inferable). Also, words are not restrictively categorized into parts
of speech: nouns used as verbs, adjectives used as nouns, and so on.
There is no copula in Classical Chinese, "是" (pinyin: shì) is a copula
in modern Chinese but in old Chinese it was originally a near
demonstrative ("this"); the modern Chinese for "this" is "這" (pinyin:
zhè).
Word order
The Classical Chinese word order is often the reverse of Mandarin; for
example, Mandarin 饒恕 (pinyin: ráoshù, "forgive") is Classical 恕饒
(Classical Chinese: ŋjew hnjas).1 [2]