Original sentence: Compound words are considered separate words with respect to vowel harmony: vowels do not have to harmonize between members of the compound (thus forms like bu|gün "today" are permissible).In addition, vowel harmony does not apply for loanwords and some invariant suffixes (such as -iyor); there are also a few native Turkish words that do not follow the rule (such as anne "mother").In such words suffixes harmonize with the final vowel; thus İstanbuldur "it is İstanbul"
Edited sentence: Compound words are considered separate words with respect to vowel harmony: vowels do not have to harmonize between members of the compound (thus forms like bu|gün (literally "this day"; in english "today", are permissible).In addition, vowel harmony does not apply for loanwords.In such words suffixes harmonize with the final vowel; thus İstanbuldur (literally "It is Istanbul").There are also a few native Turkish words that do not follow the rule (such as anne "mother") due to the fact that these are ancient words possibly introduced to the language before it aquired it's final form