My student: My family went to Tokyo Disney on Sunday.
Me: Was it crowded on Sunday?
My student: No, it was sunny.
Are you wondering what? The first time I heard something like this I might have had a big question mark in my head, but now I hear it fairly often, so I understand. The student has confused "cloud" with "crowd", the l-r thing.
It's difficult for Japanese speakers of English to pronounce, but also difficult to distinguish when listening. I have an exercise to practice listening to L and R. I have a list of similar l-r word pairs. I say three words and the student chooses which word I say twice. Example: cloud, cloud, crowd; royalty, loyalty, royalty; light, right, right.