"First, you pass by a big hospital."
Would it not be acceptable/debatably more natural to say まずは instead of はじめに
If you're wondering why there is an 大きな instead of 大きい, the former only means big, large or great and it's a pre-noun adjectival, while the latter is an i- adjective, and has other definitions
But why can't you use 大き as an い adjective in this situation? Sure it might be used for other things, but 大きい病院 should be "big hospital", even without turning it into a な adjective. Is it just more natural to use it as a な adjective than い?
using the na-adjective just kinda makes it more rhetorical or more like an opinion.
大きい病院 "big hospital"
大きな病院 "kind of a big hospital"
it's almost the same though.
It's how you show the relationship between そば and びょういん as they are both nouns. びょういんのそば means near the hospital (the vicinity of the hospital), びょういんのうしろ would be behind the hospital (the rear of the hospital).
びょういんのそばにあります means (It) is in the vicinity of the hospital (It's near the hospital), びょういんのそばをとおります means (It/you) passes through the vicinity of the hospital (You pass by the hospital).
I'm gonna take a guess and say is 初めに in kanji not being accepted, it's usually written in kana when used as a preface of a sentence, is not wrong how you wrote it though, is just less common. Probably duolingo not having it in its pool, report it next time.
初め【はじめ】transforms into an adverb as はじめに and used as an expression of "first of all"
側【そば】usually in kana, means "besides" in this context
大きな病院のそば means "besides a kind of small bank"
As a particle it is often location based particle, like "at", "by", "to", et.c.
Am I the only one constantly getting these full multiple choice sentences, often with kanji, before I have ever seen some of the words in it?