When you come to receive hundreds of messages in a day(don't you believe it?), refiling messages becomes a very tough job. Mew neatly guesses default folders where the message is supposed to be refiled when you type `o'. You can see an example below.
Folder name (+work/mew-dist): +
If the default value in () is proper, just type `RET'. The messages will be marked with `o' if its refiling folders are decided.
As you know, the more excellent refiling guess algorithms become, the less user's job troublesome. Mew provides you with the following rules.