Opinion · Listen with someone else
Karaoke keeps a different kind of score
A person singing at karaoke makes decisions faster than they can analyse them. Is the key too high? Do they know where the second verse starts? Who will take the melody if they stop before the chorus? This is a rich musical problem hiding in a room some teachers would file under entertainment.
Use one chorus to practise handoffs. One person sings the first half, another takes the second. Move the entry so both have to hear the handoff. Try the same plan in a lower key, or have one person clap while another sings. A sound that is rough but arrives at the right time can do the job.
If you are talking about karaoke with a Japanese partner, ask カラオケでよく何を歌いますか。 “What do you often sing at karaoke?” If they do not go, ask where they like to hear music. The follow-up is about an experience, and it gives both people room to bring in a story.
Most people will remember who made them feel welcome in the room. That is one of the harder musical skills to test and one of the easiest to hear when it is there.