underline

mistakes

reduce size of letters

caution writing  ( écriture ) caution presentation

OK,                 

 part of OK      ex:     +  =  1

special appreciation, encouragement, expression of satisfaction    b = bien = good  and also b = billet ( old bank note, old bank bill)   no relation with grade, just expression of one special progress.

because the student work hard on a special weakness

because in front of real difficult exercice the understanding is great even the grade is not 20

on the good way