"Is this fresh milk?"
Translation:He waiū hou kēia?
"Hou" can often be translated as "fresh", "new", or "again". In this sentence since "hou" is modifying a noun "waiū", it makes sense for it to be translated as "fresh" or "new". In the sentence "Makemake hou au i ka iʻa", "hou" is modifying the transitive verb "makemake". The whole sentence could be translated as "I want more fish" OR "I want fish again".
"He" is an indicator of equivalence. If a sentence is saying that one thing is another, the first word will probably be "he".
In this case, it breaks down to:
WORD FOR WORD
(Is equivalent to) milk fresh that
Or, A BIT MORE ENGLISH-FRIENDLY
That is equivalent to fresh milk
Or (SINCE IT'S A QUESTION)
Is that (equivalent to) fresh milk?