BOSTON (AP) - Ms Lu Lingzi was passionate about the piano, a daughter who always made her father laugh and a standout statistics student.

The Chinese graduate student was killed in the Boston Marathon blasts two days after doing well on her qualifying exams.

Friends and family on Monday night vowed not to forget the light in their lives that was extinguished too soon.

"You need us to be strong and brave," Ms Jing Li said of her roommate, who was killed as she watched the marathon a week ago. "We will keep running to finish the race for you and we will try to realise your unfinished dream."

Hundreds of people packed a hall at Boston University to say goodbye to Ms Lu, a 23-year-old graduate student.

She was one of three people killed in last Monday's bombings. Massachusetts Governor Deval Patrick was among those who showed up at the memorial service to listen to an hour of music and stories about Ms Lu.

Ms Jing told the crowd how when she met Ms Lu in April 2012, they discovered they were both from the northern part of China, both piano lovers and both without boyfriends.

"We believed we were long-lost sisters and could not wait to begin our adventure in Boston," she said. "I was so grateful that I had such a lovely sister in my life, but I had no idea that this friendship would only last one year."

Speakers recalled a bubbly young woman who loved dogs and blueberry pancakes and who was also a driven student.

Her father, Mr Lu Jun, thanked everyone for helping the family over the recent dark days before offering a eulogy "to comfort the heavenly soul of my beloved daughter."

"She was the family's Shirley Temple, if you will, the little elf and a little jolly girl, bringing everyone in the family ceaseless laughter," said Mr Lu, who spoke in his native tongue and was followed by an English interpreter.

"She's gone but our memories of her are very much alive," her father said. "An ancient Chinese saying says every child is actually a little Buddha that helps their parents mature and grow up."

Family members accepted gifts from students. They turned and bowed to the crowd at the end of the service.

Mr Eric Kolaczyk, director of the school's programme in statistics, said Ms Lu was an excellent student who passed her qualifying exams with "flying colors" just before her death. He said that though she will never achieve her goal of becoming a financial analyst, a scholarship set up in her name by Boston University will help others meet their goals.

"Lingzi's potential will instead be fulfilled by many others," he said.