Learn Turkish: Seçici insanlar ekşi sütü içmezdi. - Picky people wouldn't drink the sour milk.

İçmezdi combines the verb root iç- (to drink), the negative aorist suffix -mez, and the past tense suffix -di. Together, -mezdi expresses either a past habit ("didn't use to drink") or the negative result of a condition ("would not drink"). Here it shows what picky people would generally refuse to do in a specific situation.

Why does the sentence use sütü instead of just süt?

The -ü on sütü is the accusative case marker, which is used for specific direct objects. Because it's talking about "the sour milk" (a specific batch of milk that has gone bad), it needs the marker. If it were a general statement about sour milk, the sentence would just be ekşi süt içmezdi (they wouldn't drink sour milk).

Why doesn't the t in süt soften to d when the vowel -ü is added?

Normally, a hard consonant like t at the end of a word softens to d before a vowel suffix (this is called consonant mutation). However, many one-syllable words in Turkish, including süt (milk), saç (hair), and at (horse), are exceptions to this rule and keep their hard consonant.

How is the word seçici formed?