Questions & Answers about Hún kemur síðast á fundinn.
Because kemur is the 3rd person singular form of the verb að koma (to come).
- ég kem = I come
- þú kemur = you come
- hún kemur = she comes
So the verb has to match hún (she), which is third person singular.
Hún means she.
It is the nominative singular feminine pronoun, so it is used when she is the subject of the sentence:
- Hún kemur = She comes
Compare:
- hann = he
- það = it
Here síðast means last in the sense of last to arrive or latest.
So in this sentence it tells us the order in which she arrives:
- Hún kemur síðast = She comes last
Be careful: síðast can also mean last time in other contexts, so the exact meaning depends on the sentence.