Please fill in the following information:

Issue description

Description:  The sentence "A block device must be optionally partitioned,..." is somewhat confusing.
So does a block device have to be partitioned or not?
I did some research and it said it is optional. Then this sentence should change into somethin like:
"A block device can be optionally partitioned,..."

Or I am mistaken and something else is meant here.
Thanks for the clarification. 

Revised

=======

A block device can optionally be partitioned before use. Whether partitioned or not, a file system must be created on the device (or partition) before it can be mounted.

Steps to reproduce:

Workaround:

Expected result: