I want to know how many cups of coffee a person can drink in one day and still be healthy.
Up to how many cups of coffee a day would be considered reasonable for a person to drink.
ーI want to know how many cups of coffee a person can drink in one day and still be healthy.
「１日に何杯のコーヒーを飲んでもまだ健康でいれるか知りたい。」
how many cups of coffee a person can drink in one day で「１日何杯のコーヒーを飲むことができるか」
ーUp to how many cups of coffee a day would be considered reasonable for a person to drink.
「１日に何杯までコーヒーを飲むのが適切だろう。」
Up to how many cups of coffee a day で「１日に何杯のコーヒーまで」
ご参考まで！
カナダ 
