Pretoria, South Africa (CNN) -- An emotional Oscar Pistorius apologized Monday to the family of Reeva Steenkamp, the girlfriend he killed on Valentine's Day last year, saying he woke up thinking of them and praying for them every day. 

"I would like to take this opportunity to apologize -- to Mr. and Mrs. Steenkamp, to Reeva's family -- to those who are here today who knew her," Pistorius said as he took the stand for the first time at his murder trial. 

"I can't imagine the pain and the sorrow and the emptiness that I have caused you and your family. ... I can promise you that when she went to bed that night, she felt loved," he said, his voice breaking as if he was fighting back tears. 

It was the first time he has spoken in public about Steenkamp's death, which he says was an accident. He pleaded not guilty to murder when the high-profile trial opened last month. 

Steenkamp's mother, June, sat stony-faced in court as South Africa's onetime Olympic golden boy choked out his statement. 

Judge Thokozile Masipa also betrayed no emotion as Pistorius spoke but did once ask him to talk louder, saying she could hardly hear him. 

Monday was the first day of the defense phase of the trial, following three weeks of prosecution in March. 

Pistorius, who says he mistook Steenkamp for an intruder in his house in the dark, testified that he has been suffering nightmares since the killing and wakes up smelling blood.  QUESTIONS:

Q1:
1. Where is this report taking place?
2. Where is the report coming from?
3. 
Q2:
1. What is happening in the report?
2. What incident is the news report describing?
3. 
Q3:
1. What was the name of the woman who was killed by Oscar Pistorius?
2. What was the woman who was murdered by Oscar Pistorius called?
3. What was Oscar Pistorius's girlfriend's name?
Q4:
1. When did Oscar Pistorius kill his girlfriend?
2. When did Oscar Pistorius murder Reeva Steenkamp?
3. When was Reeva Steenkamp killed by Oscar Pistorius?
Q5:
1. What phase is Oscar Pistorius's trial in?
2. What phase is Reeva Steenkamp's murder trial in?
3. Oscar Pistorius's trial is in what phase?
Q6:
1. Did Oscar Pistorius say anything?
2. Did Oscar Pistorius talk in public?
3. 
Q7:
1. What did Oscar Pistorius say?
2. What did Oscar Pistorius say in his public appearance?
3. 
Q8:
1. What did Oscar Pistorius say happened on the day he killed his girlfriend?
2. How did Oscar Pistorius describe the events of the night he killed his girlfriend?
3. What did Oscar Pistorius say happened during the incident where his girlfriend was killed?
Q9:
1. How long was the first phase of Oscar Pistorius's trial?
2. How long did the first phase of Oscar Pistorius's trial last?
3. 
Q10:
1. Why was Oscar Pistorius's trial a high profile trial?
2. Why was Oscar Pistorius's trial so well-known?
3. Why was Oscar Pistorius's trial popular?
Q11:
1. Where was Oscar Pistorius from?
2. What country did Oscar Pistorius play for?
3. What country did Oscar Pistorius win a medal for?
Q12:
1. Who was presiding over Oscar Pistorius's trial?
2. What was the name of the judge who was overseeing Oscar Pistorius's case?
3. Which judge was presiding over trial of Oscar Pistorius?
