Is it possible to change the format - lines are too long and it is difficult to rad responses.
The length of lines is set by your browser. If you set your browser to be wide, you will have long lines. Make the browser window narrow, and you will have narrow lines.
There is an exception to this. If there is a very-long-word (often a url), or a wide image, the browser will use that to set the line length. Admins usually notice these problems, and shorten the url (or its appearance), and use a thumbnail to reduce the image size. If you notice a message that needs shortening, post a note to the moderation thread (with a reference to the wide post).