Red fon​      = Remove/omit the red colored part.

→               = Indent the sentence.  

Lower case​= Change the letter(s) to small letter(s).

UC             = Change the letter(s) to big letter(s).

NR             = No error/mistake

WB             = Wrong abbreviation

WS             = Wrong Spelling

AP              = Add punctuation mark(s)

FR              = For revision

↗              = Start a new paragraph

#               = Add a space​

×​           ​ = Remove a space​

∽​             = Transpose (change the position of the word) 

SF              = Sentence Fragment

AW             = Add a word (noun/pronoun/preposition/verb)

MP  ​                 =  Misused preposition. ​