Questions & Answers about Bugün kafam iyi değil.
Why does this sentence use değil instead of değilim if the English translation is often 'I am not...'?
The grammatical subject in this sentence is kafam (my head), which is a third-person 'it'. Even though the overall meaning relates to how you feel, the literal Turkish structure is 'my head is not good'. Therefore, değil is used by itself and doesn't take the first-person -im suffix.
Does kafam iyi değil just mean 'I have a headache'?
Since we are learning the duration suffix -DIr, could I say Bugündür kafam iyi değil to mean 'My head hasn't been good today'?
No, you wouldn't use -DIr with bugün here. The suffix -DIr attaches to a measured amount or duration of time (like üç gündür meaning 'for three days'). Bugün (today) points to a specific timeframe rather than a duration, so it doesn't take the suffix.
What is the -m at the end of kafam?