Given a document, find the main entity about whom the author is writing. Write the full name if mentioned in the text. Note that URLs in the text have been replaced with [Link].

[EX Q]: Sam Querrey gave the United States a winning start in its bid to reach Saturday's final at the World Team Cup.
 Querrey beat Jan Hajek 6-3  7-5 on Thursday to put the U.S. 1-0 up against the Czech Republic in the Red Group and remain unbeaten in his three singles this week.
 "So far so good " said Querrey. "I thought today was the best I played out of the three matches. So I'm pretty excited."
 Hajek claimed the first break  when Querrey ended a long rally with a forehand error  to go 3-1 up but the American player responded by winning the next five games in a row to take the opening set.
 Both players saved a break point late in the second set before Querrey broke at 6-5  converting his third match point.
 "I've been working this week to try and hit my forehand a little bigger. I felt I did that today " said Querrey. "I felt pretty much anytime I got a forehand  I was able to take control of the point."
 Querrey said his win takes the pressure off the U.S. ahead of Friday's matches.
 "A little bit  yes. I think John (Isner) can go out there and play a little more freely  which is a good thing " Querrey said. "When we have the lead  you can swing away a little bit more than if we were 1-0 down.
 "Then  the Bryan brothers  we expect them to win every match. Hopefully  they are going to do that again."
[EX A]: Sam Querrey

[EX Q]: Watch CBN News' Heather Sells interview with  Sadie Robertson  about  her  latest book and what's next for  her .
 Sadie Robertson  is well known for  her  captivating smile and role in the reality TV series "Duck Dynasty"
The show ended last year but the 20 year-old continues to make a name for  herself .  She  has acted in God's Not Dead 2  danced  her  way to first runner up on Dancing with the Stars  and continues to inspire fans and share  her  faith on YouTube.
Now  she 's traveling the world and sharing how  she  learned how to conquer fear in  her  new book  "Live Fearless."
"I used to live in a lot of fear. I had a lot of anxiety and really dealt with panic attacks - the whole nine yards. Anything fear  I was totally living in it. It was actually in the season of my life when I was very  very public  " Robertson  told CBN News. " I don't feel like people were really seeing the fullness of who I was because I was so afraid."
Despite  Robertson 's life being so public   she  was engaged in a very private war against fear for years until  she  learned how to beat it.
"Finally  I found freedom through my faith and totally over fear. All of a sudden  I become a totally different person. I start speaking all of a sudden. I'm a lot more confident in what I'm saying. I have a lot more life  more joy-filled  and people started to see the change in me "  she  said.
 Robertson  says one of the biggest ways to fight anxiety is to take every fearful thought into captivity.
"You can be in like  literally  a room where there's no fear around you but because your mind is so consumed with fearful thoughts. It's really a mind thing. And so  really finding freedom and captivating the thoughts of your mind is a huge way out of it "  she  shared.
 Robertson  wrote this book for anyone who struggles with fear like  she  did.
 Robertson 's life hasn't shown any signs of slowing down since  she  wrote  her  book.  She  recently completed  her  "Live Original Tour" which brings thousands of young people together to worship God and learn how to live as He created them to be.
[EX A]: Sadie Robertson

[EX Q]: Whenever such a chance presents itself  I pick homies who've never flown before. (Recently  on a trip to Washington  D.C.  one of them asked  “Are we flying Virgin Airlines because it is our first time?”) When I went to Spokane  I took  Mario  and Bobby.
We flew out of Burbank  where passengers walk onto the airport tarmac and go up stairs to get into the planes. Of the hundreds of first-timers I've traveled with over the years  no one has ever been as terrified as  Mario .  He  was gasping and flushed — and we were still inside the terminal. Out the window I could see flight attendants climbing the stairs  each holding two Venti-sized drinks.  Mario  emerged from  his  terror tunnel long enough to ask  in a panicky whine  “When are we gonna board?”
 Tall and gangly  Mario  may be the most tattooed individual ever at Homeboy.  He  is all “sleeved out ” neck blackened with the name of  his  gang and  his  entire face covered in tattoos. I had never been in public with  him   and I watched as people sidestepped us in the airport. Mothers pulled their kids in tightly. The recoiling was pronounced and widespread. And yet  everyone at Homeboy would agree that  Mario  is the gentlest of men.  He  calmed  himself   and we got to Spokane without event.
At Gonzaga  the auditorium was full  maybe 1 000 people.  Mario  and Bobby spoke first. Nervous (again)  hands and voices shaking  they told their stories of violence  terror and abuse of all kinds. Honest to God  their words were like flames; you had to keep your distance or get scorched.
I asked Bobby and  Mario  to join me for the question-and-answer period. A woman near the front spoke first.
“You say you're a father ” she said to  Mario   “and your son and daughter are starting to reach  their  teenage years. What wisdom do you impart to  them ?” She recalibrated. “What advice do you give  them ?”
She sat  and  Mario  sifted her words  looking for a response. “I just ...”
There wasn't much of a pause before the audience stood and began to clap.  All Mario  could do was hold  his  face in  his  hands.
[EX A]:
Mario