1. entirely; completely -> Altogether. 
2. A state in the United States -> Arkansas, the 25th state of the US. 
3. One who is sent out on a mission -> Apostle, but more commonly known as a missionary (person on a mission). 
4. An advantage -> Benefit, As a advantage would be beneficial to yourself or to the designated person. 
5. At every time -> Always. 
6. Feelings of sympathy -> Compassion, which by definition, is having sympathetic pity or concern for the misfortunate. 
7. A pronoun referring to any object, occurrence, or matter -> Anything. 
8. A shortened form of a word or phrase -> contraction, which by definition means to shorten. 
9. To accept as true or real -> Believe. To believe something to accept it is true, regardless if it is really the truth or not.
10. One who comments upon or discusses issues -> Commentator. Note the usage of Commentator, -ator implying a person, and so it is a person who comments. 
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