E.g. Complaint by telephone and then by letter in writing. Spoken Prose - scripted in advance, read or recited, speaker may be in visual contact with audience, not created spontaneously. The Ss who you enjoy teaching read ahead. Even if the teacher doesn't write, the Ss will try to write. It's the only way they can keep a record.
Copying is a very complex activity.
When people copy they make mistakes. Copying trains muscular memory. These exercises are a good test of structurak knowledge. Dictation - n.b. There are many forms of dictation.