What would an exclamation mark at the end of the word OK mean?
It might mean that the person is shouting okay or that they are irritated.
OK! I'll do it. Just stop bothering me!
In a sentence if an exclamation point is within the sentence do you capitalize the word following the exclamation point?
Ending a phrase with the term 'good luck' does not require the use of an exclamation mark. The use of an exclamation mark is dependent on the meaning or tone of the sentence, not the use of any particular word or phrase. There are instances in which the use of an exclamation mark after the phrase 'good luck' may distort the intended meaning, such as, 'I have not had good luck'.
The inverted exclamation point can be entered by holding down the Alt key and pressing 0161, 173 or 8877 on the number pad. In Microsoft Word, the inverted question and exclamation marks can be typed by holding down the Ctrl, Alt, and shift keys while typing a normal question or exclamation mark, or by typing either mark at the start of the sentence whilst in the Spanish language mode.