Here’s an extract from Genki Lesson 10 reading practice:
おじいさんは「おじぞうさん、さむくないですか。」と聞きました。
I thought 聞く referred to hearing something. But then why would you say the grandfather heard something when he was the one saying it? I thought you would use 話しました/言っていました instead of 聞きました.
I’m definitely missing something and appreciate any help in advance.
聞く is used both for hearing and asking, so in this case he’s asking.
Oo I didn’t know. So would you use 聞く when you want to ask anything in general?
Not when you want to ask a question, but you would use it to talk about asking as in:
I will ask Keisuke.
圭介に聞く
or
I’ll go ask Sensei
先生に聞いてくる
おr,
I asked, “why?”
「なんで」って聞いた。
I’m not the best person to ask about nuance or when to use certain words since I don’t have any experience conversing in Japanese. As far as I know 聞く can be used in general for asking. Another word that can be used for asking is 尋ねる. Beyond that I have no idea, so I would definitely wait for someone else to confirm or give more detail.
I see, thank you for the examples they really help!!
No worries, you’re initial answer really helped clear my confusion in the moment and let me finish the exercise. So I have to thank you for your quick response as well!!
聞く can be used very broadly. 尋ねる sounds more formal, and its smaller scope (it can’t mean “listen” the way 聞く can) means that it often gets used when clarity is important, for instance in a foreign language textbook.
Other verbs for asking:
問う - often used for more abstract questions, or with a sense of investigation
伺う - humble verb for asking people in superior social positions to you (don’t worry about using it, but just note that it exists)
質問する - basically exactly what it looks like, the する-verb version of 質問
Apologies for the late reply 
, but thank you for those extra words + usages. That’s given me a good feel for when to use what. 