What does "better still" mean here? Is it something like slang?
Native speaker’s answer
Rebecca
"Better still" is an expression that is used when you want to include another idea on top of a previous one that you think is better. You can also say "better yet". Ex: Add some lime or better still, some lemon juice. Ex: If you buy a guitar or better yet, an electric guitar, you can plug it into an amp and play it loudly.