|Alvin Cheng Kam-mun|
|Other names||Alvin, "4 Eyes Brother"|
|Education||Queensland University of Technology|
|Known for||Umbrella Movement|
|Political party||Student Front (dissolved), Civic Passion|
Alvin Cheng Kam-mun (Chinese: 鄭錦滿), also known as nickname "4 Eyes Brother" (Chinese: 四眼哥哥), is a Hong Kong student activist and active from 2014. He formerly studied at Queensland University of Technology, and organised a rally with his schoolmate and Nardo Wai in support for the Hong Kong Umbrella Movement during 2014 G20 Brisbane summit. His political opinion is using violence to fight against police force. He is well known for participating in the Hong Kong Umbrella Movement and establishing student activism organisation "Student Front".
On 22 September 2014, when Hong Kong Umbrella Movement started, Alvin, who was studying in Queensland University of Technology, saw the news that student protesters had been arrested in Hong Kong. He then went back to Hong Kong to participate in the protest.
On 16 November 2014, Alvin and Nardo Wai started their 4-hour rally in support for the Umbrella Movement on the lawn near the South Bank Parkland Suncorp Piazza outside the G20 summit venue. Numerous oversea students from Hong Kong, Taiwan and Mainland China participated in the rally.  After organising the rally, Alvin went back to Hong Kong again to continuously participate in the Hong Kong Umbrella Movement.
On 6 December 2014, Alvin established "Student Front", a student activism organisation, to fight against the "stage power" and keep staying in the front line after Hong Kong Federation of Students and Scholarism quit from the protests. He was arrested on suspicion of attending and inciting others to take part in an illegal assembly. He wrote an article indicated that he was arrested on 26 December 2014 and failed to be bailed. After Umbrella Movement, Alvin continued participating in numerous social activities, such as Gau Wu and the movement fighting against parallel trading. He was arrested several times and difficult to be bailed. He was then banned to enter Mong Kok by a court order.
On 2 March 2015, Alvin announced that Student Front was dissolved, and warned other activists not totally depend on "student activism organisations". On 23 March 2015, Alvin was in court for his arrest in the end of 2014. In the morning of 27 April 2015, Alvin was engaged in conflicts with supporters of Avery Ng, the vice-chairman of League of Social Democrats, outside Mongkok Police Station because of disputes in Umbrella Movement. 
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