The 24-year-old was killed during a robbery in Hyde Park. Zheng's life was honored at the University of Chicago Rockefeller Chapel, where he was a recent graduate and teaching assistant of statistics.
SEE ALSO | Man charged with murder of University of Chicago graduate killed in Hyde Park shooting
"We are heartbroken by this tragic and senseless loss which has been felt deeply by our community both here in the United States and around the world," University of Chicago President Paul Alivisatos said.
"Although his life was cut short, Dennis had an extraordinary impact on this world and on the many people who knew and loved him," University of Chicago Provost Ka Yee C. Lee said.
Last Tuesday, the 24-year-old was killed during a robbery in the Hyde Park neighborhood. The incident was the third violent crime involving a U C student this year.
SEE ALSO | UChicago staffer robbed at gunpoint blocks away from shooting that killed grad earlier this week
Earlier this week, some students and faculty rallied for better security. And on Wednesday night, a forum on campus was held with Chicago Police Supt. David Brown, during which he shared new strategies combat crime.
At Thursday's service, China's Deputy Consul General for Chicago Zhichun Bian urged Chinese students in Chicago and across the US students to take precautions.
"The Chinese consulate general in Chicago will spare no efforts to serve our compatriots," Bian said.
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Some friends of Zheng's and those familiar with the campus want to see more protections for students.
"It's just shocking because it's so sudden and in a relatively safe area," Zheng's friend and recent U of C graduate Colin Xie said. "It's right across from the field."
"There are still students who live, not on campus, but close to campus, and they don't have any measures to make sure they are secure and safe," said Arlene Tang, who graduated in 2017.
Zheng's parents came from China for the service. Zheng was the couple's only child.
Zheng's mother's remarks were translated for ABC7 by the Chinese American Service League:
My dearest son, I carried all my tears, all my longingness for you and all my sadness, and traveled all the way and finally arrived at the University of Chicago, where you chased your dream. This is the first time that your mom ever traveled outside of China. But this is not for sightseeing, not for attending your graduation, and not for your wedding, but for your funeral, what a cruel tragedy!
I can still vividly see the joy on your face the day you started out on your journey. You told me that you are going to show me the world in the future. You wanted me to witness your dream come true and you wanted us to look forward to the future. However, look at what happened now, we are separated by heaven and earth. I have desperately been trying to call you by your name again and again. Son, tell me why when I just begin to see hope I was thrown into hell a moment.
My poor son, when the evil bullet hit your young chest, when you were lying with blood all over your body on a foreign soil, you must felt so helpless in that cold street. Helplessness, hopelessness and anger must have filled in your heart. You were only 24 years old! Your dream of science, your dream of astronomy, your dream of math and your dream of love, all of those were shattered at that moment. You and your longingness for life, your love for your family, and your care for your fellow students, all disappeared entirely from my life with that murder's bullet.
All of this happened too fast, I was shaking and heartbroken the moment I heard the news. I wished to die and did not want to believe this. I didn't want to believe that I would no longer be able to see my baby. People always say those who bring light and hope to other people are the angels. So God, I beg you, please return my angel back to me.
In this short 24 years, you gave me so much joy and I have enjoyed every moment bringing you up. In order to pursuit your dream, you studied hard, from LeShan middle school to Chengdu No7 high school to Hong Kong University and finally to the University of Chicago. You have completed your graduate school with stellar performance. I feel so proud of your achievements and you feel grateful for my support.
Just two days before you were shot, I received a bottle of perfume that you sent from Chicago. This is the birthday gift you bought for your mom, so today I am wearing this perfume and I believe you can smell it as well as the smell of your mother. You know that mom is coming to take you home. I will stay with you quietly and use the comb from your childhood and comb your hair again and again. I will caress your handsome face and kiss your wise eyes, and hope you can open your eyes just one more time to look at your mom who loves you so deeply. I want to hug you tightly and warm your cold body with mine. I am going to take you home.
Son, do you know that every time I hear other people compliment you, I feel so proud. In other people's eyes, you are this wonderful perfect person so gentle and kind. You are like the sunlight, bringing warmth to others. But I know all the hard work and efforts you have put in to achieve your success. I am so proud of you, son.
One thing that brings some comfort to me during this darkest moment of my life is that countless people, some of whom I don't even know before, have come to me and gave me love and support. The Consul General of China in Chicago and the University of Chicago both called me and sent their support; Hong Kong University and Chengdu No7 high school have organized memorial for you and countless of others have all came to help. It is those people's love and support that helped me overcome challenges to be able to come to see you today. So I would like to thank them on your behalf.
Dear son, thousands of mothers and thousands of friends and relatives have all come with me today. We share the same sadness, we share the same anger and we have the same demand: bring the murder to justice! I hereby call to action that we need to make sure that every single foreign student's safety be protected and we must prevent this kind of tragedy from happening again. This is the demand from thousands of foreign students and their families as well.
Son, with all the people's love, I wish you a smooth journey in Heaven.