Use is/are for SHACL and MUST for processors / remaining issues

Hello,

according to our resolution, I took an attempt to work on this task.
https://github.com/w3c/data-shapes/commit/cf0edb9715b7e5de8ba500b37285c96c62d5e9dc

any feedback is welcome.

There are two issues remaining
(1) what do we do with "should" / "may"? we can continue with is/are and
add clarifications that the SHACL processor should / may but gets too
verbose

 (2) how do we describe examples? (I removed must from there but we need to
be consistent)
e.g. we have
 - The property <code>sh:class</code> can be used to verify that each
<a>value node</a> is a <a>SHACL instance</a> of a given type.
 -  each person (<code>bf:Person</code>) needs to be identified
by (<code>bf:identifiedBy</code>) exactly one identifie
 - The property <code>sh:maxLength</code> restricts the string length of
<a>value nodes</a>
 - String value that an IRI has to start with
 - each <a>member</a> of the list specifies conditions on a subset of the
value nodes and may contain the following parameters
 - require that a focus node be an IRI

meaning we use different terms: verify, needs to, has to , specify, require
and maybe others I missed.
What should be the proper term to define the intention of SHACL?

Best,
Dimitris
-- 
Dimitris Kontokostas
Department of Computer Science, University of Leipzig & DBpedia Association
Projects: http://dbpedia.org, http://rdfunit.aksw.org,
http://aligned-project.eu
Homepage: http://aksw.org/DimitrisKontokostas
Research Group: AKSW/KILT http://aksw.org/Groups/KILT