edit top-level resource section

Combined the text from the pattern to the top-level resource section.

docs/eml-semantic-annotations-primer.md

@@ -52,9 +52,9 @@ The second annotation has as its subject the `attribute` element with the `id` a
 
 The top-level resources in EML are dataset resources, literature resources, protocol resources, and software resources. The resource types share some common information, such as title and creator, but also contain information that is specific to a particular resource type. Note that the dataset module can import the other top-level resources at different levels. Further information about top-level resources may be found in the [eml-resource module] section.
 
-[eml-resource module]: eml-modules-resources.md#the-eml-resource-module---base-information-for-all-resources
+[eml-resource module]: eml-modules-resources.md#the-eml-resource-module---base-information-for-all-resources 
 
-A top-level resource annotation represents a precisely-defined semantic statement that applies to one of the top-level resources. This semantic statement is used to associate precise measurement semantics with the resource. An `annotation` element is embedded in a containing resource element. The subject of the semantic statement is the resource element that contains the annotation. If the resource element contains an `id` attribute, then the subject should refer to the value of the `id` attribute. Each annotation consists of a `propertyURI` element and `valueURI` element, which respectively define a property and a value (object) that apply to the resource. Each URI should resolve to a controlled vocabulary that provides a precise definition, relationships to other terms, and multiple labels for displaying the statement. The associated `label` attribute for each URI can be used to display the property and value in a more readable format to users. Ideally, each `label` should be populated by a preferred label or label from a controlled vocabulary.
+A top-level resource annotation represents a precisely-defined semantic statement that applies to one of the top-level resources. This semantic statement is used to associate precise measurement semantics with the resource. An `annotation` element is embedded in a containing resource element. The *subject* of the semantic statement is the resource element that contains the annotation. *It is recommended to give the subject element an* `id` *attribute and refer to the subject by the value of the* `id`. Each annotation consists of a `propertyURI` element and `valueURI` element, which respectively define an *object property* or *data property* and the *object* (value) of the annotation. *The URIs should ideally point to terms in controlled vocabularies* that provide precise definitions, relationships to other terms, and multiple labels for displaying the statements. The `propertyURI` and `valueURI` elements can each have a `label` attribute that displays a more readable label suitable for application interfaces. *It is recommended that the labels are populated by values from the preferred labels field (skos:prefLabel) or label field (rdfs:label) from a controlled vocabulary*.
 
 In the following dataset annotation (Example 2), the subject of the semantic statement is the `dataset` element containing the `id` attribute value "dataset-01". The object property of the statement is "http://purl.org/dc/elements/1.1/subject". Finally, the value (object) in the semantic statement is "http://purl.obolibrary.org/obo/ENVO_01000177", which resolves to the "grassland biome" term in the ENVO ontology (http://www.obofoundry.org/ontology/envo.html). Taken together, the semantic statement could be read as "the dataset with the id 'dataset-01' is about the subject grassland biome".