As a non-English speaker whose native language does not have articles I am always unsure about the use of them. This time I would like to clarify the use of the article "THE" together with positions of persons. For example:
John Smith and the director of my department Adam Gray went to a meeting yesterday.
If I state the name of the person do I need "THE"? I understand that if I said just "John and the director of my department went..." "THE" would be necessary but does that change when stating the name also?
Similarly, do I need to put "THE" in this type of sentence:
The Prime Minister of the United Kingdom David Cameron announced changes in immigration policy.
If I don't need the definite article here then why so? Are the two examples equal?