Quintilian and Isidorus about barbarian langauge

The source I used is the same as in the text with Herodot. For
confirmation or rejecting I will be very thankfully.
Too, I will be very thankfully for a translation of the latin
texts in one of better to understand langauge, like english
for instance:-)

Quintilian Inst. I 5. :
barbarismum pluribus modis accipimus.Unum, in gente, quale
sit, si quis Afrum vel Hispanum Latinae orationi nomen
inseart... Tertium est illud vitium barbarisimi... ut verbo,
cuilibebit, adjiciat litteram syllabamve vel detrahat; aut
aliam pro alia, aut aemdem alio, quam rectum est, loco ponat."

Isidori Orig. I 31.1
Appelatur autem barbarismus a barbaria gentibus, dum orationis
latinae integritatem nescirent.
-ibid I.31 3:
Barbarismus autem fit scripto et pronunciatione.Scripto... si
quis in verbo litteram vel syllabam adiiciat, mutet,
transmutet vel minuat.Pronunciatione autem fit in temporibus,
tonis, aspirationibus etc.