According to Guinnessworldrecord.com, the most piano key hits in one minute is 824, achieved by Domingos-Antonio Gomes (Portugal) in Lisbon, Portugal, on 4 March 2017. I knew this sentence has to be grammatically correct, but I still have two questions:
1) Why is the word "hit" used as a third-person singular form? I thought it should be used as a past participle ("hit"), in order to form the perfect tense, like "the biggest cake made by a human being" or "the funniest joke told by my father". Is it because "hit", in this case, is a predicate verb (whose subject is "key") and not a postpositive determiner？But shouldn't the subject of a hit be a person?
2) Why is the word "key" in the singular form here? Since it is modified by "most", I thought the countable noun "key" should be put in plural form (keys), like "the most votes I've ever got".
Can someone explain that to me? Thanks so much.