In the following explanations, an asterisk before a word indicates an incorrect form.
AC = "accord," agreement error.
AN = "anglicisme abusif," an error in French resulting from the literal translation of an English idiom, expression, or construction.
AR = "article," wrong article (frequently the definite article where the partitive article du, de la, des is required; sometimes des when de or d' is required, as in d'autres).
AU = "aussi," do not start a sentence or clause with the word aussi meaning also; either place the word aussi after the verb or auxiliary, or alternatively replace it with De plus (En plus in conversation) or D'ailleurs at the beginning of the sentence. At the beginning of a sentence or clause the word aussi means therefore, and is usually followed by the inverted form of the verb and subject pronoun: Aussi dit-il... = Therefore he says...
AX = "auxiliaire," wrong auxiliary for the passé composé or other compound tense (frequently avoir where être is required).
CN = "contraction," contraction required (e.g., du for *de le).
CS = The grammar textbook Contrastes
DC = "documentation," indicate clearly in a footnote the source of this statement or idea (author, title, edition, place of publication, publisher, page numbers).
D1, D2, D3, D4 = Vous n'avez pas corrigé cette erreur selon point numéro 1 (ou 2, 3, ou 4) de votre Déclaration signée.
GN = "genre," gender error.
GR = "grammaire," miscellaneous grammatical errors.
IC = "incohérent," what you have written here does not make sense or is difficult to understand.
IN = "indicatif," put this verb in the indicative instead of the subjunctive (frequently after the affirmative form of verbs like croire, penser, espérer , when the subjunctive is used only after the negative or interrogative form of such verbs).
NM = "nombre," number or singular/plural error.
OM = "omission", OM/AR = omitted article, OM/PR = omitted preposition, etc.
OR = "orthographe," spelling error.
PM = "pronom," wrong pronoun (frequently a disjunctive pronoun where an indirect object pronoun is required, as in Il a parlé *à elle where one should read Il lui a parlé; sometimes the wrong form of the pronoun, as avec *leur for the correct form avec eux, or Il *leurs a parlé for the correct form Il leur a parlé; often the wrong relative pronoun, such as qui for que or dont and vice versa: les choses *qu'il a besoin for les choses dont il a besoin).
PM--->C.O.D. "complément d'objet direct," change this to a direct object pronoun (for example, to le or la).
PM--->C.O.I. "complément d'objet indirect," change this to an indirect object pronoun (for example, to lui).
PN = "ponctuation," punctuation error.
PO = "position," this word is in the wrong place (frequently an adverb that should be placed immediately after a verb or an object pronoun that is the wrong place -- consult your grammar).
PR = "préposition," wrong preposition after this verb or with this noun (often de for the correct pour meaning "in order to" before an infinitve).
PS = "passif," put this verb in the passive (e.g., for the incorrect form Cette oeuvre *a écrit par Molière write the correct form Cette oeuvre a été écrite par Molière. Check your grammar if you are unsure of how to form the passive. Remember that in the passive the past participle must agree in number and gender with the subject of the verb).
RG = "registre," wrong level of language for this type of discourse (e.g., ça where cela is required in an academic essay).
RP = "répétition," unnecessary repetition of ideas or words.
SJ = "sujet," these statements are wandering away from, or are irrelevant to, the precise topic you have chosen or been assigned for this essay.
SU = "subjonctif," put this verb in the subjunctive, and with the aid of your grammar determine why.
TM = "temps," tense error (some fundamental rules: (1) passé composé for events taking place at a specific time or within a defined period of time; (2) imparfait for ongoing or repetitive situations or states of mind; (3) plus-que-parfait for events that occurred prior to other past events; (4) future after expressions like quand and aussitôt que when the action referred to by the verb will take place in the future).
TR = "traduction," incorrect translation (i.e., what you have written is grammatically correct, but it does not accurately translate the English word or expression in question).
TS = "transcription," copying error.
VG = "vague," your meaning is not clear because what you have written here is not precise enough.
VO = "vocabulaire," vocabulary mistake; check both the English-French and French-English sections of the Collins-Robert unabridged dictionary, and possibly a good unilingual French dictionary (Petit Robert, Larousse, Bordas).