Part/whole
A casing is part of the sausage that holds the meat
A word or phrase that modifies a word not clearly stated in the sentence. A modifier describes, clarifies, or gives more detail about the concept
You can organize a sentence by making sure you have all of the parts of a sentence written out, so when you write your sentence out, you know you have a complete sentence.
For sites 1 and 2 I'm not sure what you mean.
