Learn Turkish: Yemekler harikaydı, servis hızlıydı; kısacası her şey mükemmeldi. - The food was wonderful, the service was fast; in short, everything was perfect.

While hatta escalates or adds a surprising extra point, kısacası summarizes what was just said. It comes from kısa (short) and means 'in short'. You would use hatta if you were escalating a single point, like 'Yemekler harikaydı, hatta mükemmeldi!' (The food was wonderful, in fact it was perfect!). Here, we are summarizing multiple good things instead.

Why do harikaydı and hızlıydı have a 'y' before the past tense ending, but mükemmeldi doesn't?

This is a reminder of how the past tense form of 'to be' (-di/-dı) works. Because harika and hızlı end in vowels, we need the buffer letter -y- to attach the suffix (harika-y-dı, hızlı-y-dı). Mükemmel ends in a consonant, so the suffix attaches directly (mükemmel-di).

How is the word kısacası formed?

It is built from the adjective kısa (short). It gets the adverb-forming suffix -ca and the possessive suffix -sı. You can think of it as literally meaning 'the short of it.' It is a very common set phrase used to wrap up or summarize a thought.

Does her şey (everything) always take a singular predicate like ?