Learn Turkish: Dün otobüsü kaçırmadım. - I didn't miss the bus yesterday.

It is built by adding suffixes to the verb root kaçır (miss). We add ma (the negative suffix), then dı (the past tense suffix), and finally m (the personal suffix for "I"). Put together, you get kaçır-ma-dı-m.

Why do we use "-madım" for the negative past tense here instead of "-medim"?

Turkish uses vowel harmony to match suffixes to the word before them. The negative suffix is either ma or me. Since the last vowel in kaçır is the undotted 'ı', we use ma. Because ma ends in 'a', the past tense suffix that follows it will always be dı. This gives us -madım.

Why is there an extra "-ü" at the end of "otobüsü"?

The -ü is the accusative case suffix, which is used for specific direct objects. Because you are talking about "the bus" (a specific bus) rather than just "a bus", otobüs needs this suffix. It is -ü to match the final 'ü' in otobüs.

Where is the Turkish word for "I" in this sentence?

In Turkish, the subject is already built into the verb. The -m at the very end of kaçırmadım means "I". You could say Ben dün otobüsü kaçırmadım, but the pronoun Ben is optional and usually dropped in everyday speech unless you want to emphasize it.