"It is 4:04."
When giving the hour, 4, 7 and 9 are exceptions, they are : 四時(よじ) Yoji 七時(しちじ) Shichiji 九時(くじ) Kuji
When giving minutes, the kanji 分 is read as ぷん(pun) in the following exceptions: 一分(いっぷん) Ippun 三分(さんぷん) Sanpun 四分(よんぷん) Yonpun 六分(ろっぷん) Roppun 八分(はっぷん) Happun 十分(じゅっぷん) Juppun
I've been seeing conflicting messages in other threads about 4 minutes. Some have said "yonpun", like you. Others have said "yonfun".
I Googled it and one response from a teacher on yesjapan.com forum said that both pronunciations are acceptable but "yonpun" is more common.
Hope that helps anyone who was confused like me!
When you add です to the end of a sentence, it shows that it's polite and/or that you're answering a question. If the question was 何時ですか , then you will answer with です as a 'it is _ o'clock'. Also the other question may have been asking what 時 meant, so you just needed to translate it into english, or the other way around.