The phrase "Yes Sir" is normally used when a male older than you asks for your attention or if they ask you to do something. Normally it is said to someone you respect.
The Navy has developed a whole language of its own over the centuries. Typically someone that has been given an order will respond with Aye, Sir! or Aye Aye, Sir! The single Aye is normally used with a repeated order, such as "Aye, Sir! Coming to heading 240, Sir!" where is Aye aye is used independent of anything else. A commanding officer, and only the commanding officer, can reply, Wilco! Which is short for "Will Comply."
Mr. President is the normal title used. Sir is appropriate, as in Yes, Sir and No, Sir.
"Yes, Sir!" is an exclamation. It is used to show deference to elders.It is also a required reply in the US Military.
It is capitalized when it is a title, meaning it comes before a name, but not as a pronoun, where it takes the place of a name. For example in Sir Elton John the Sir is capitalized, but in the sentence, "Hello sir," the sir would not be capitalized.
Yes. It is a prepositional phrase, used as an adverb.
Yes, the term "aye aye, sir" is still used in the Marines as a way for service members to acknowledge an order or instruction. It signifies that the order is understood and will be carried out. While the phrase is traditional, variations may exist depending on the context or the specific unit.
Yes
YES!
No, unless you're calling someone it or that is their name. For example, Sir Henry of Yorkshire, or if they are just called sir like the football player.(It was spelled with two R's though.)
Yes, although a more common phrase used is "normally abnormal" - in absolute terms the lesion described is abnormal but is it a commonly seen lesion that does not clarify or impact the diagnosis.
Yes. The prepositional phrase can be an adverbial phrase. Example: We do not play in the office.
Yes, "can be used" is a grammatically correct phrase that is commonly used to indicate something that is acceptable or able to be utilized for a particular purpose.