498
In order to improve the epidemic control , Secretary for Social Affairs and Culture Chui Sai On , who has been named director of the SARS task force by the government , has designated representatives from the Health Services and the Center for Disease Prevention and Control to visit neighboring Guangdong Province on Thursday , to learn from Guangdong ' s experience and know - how in combating SARS , which have been acknowledged by WHO .
 Chui Sai On: person; government: agent
Given event type and trigger, please tell me the arguments of all the listed option. Output format is "name1: role1; name2: role2". 
Event type: nominate 
  Option: person, agent 
Text: {0} 
Answer:
 Chui Sai On: person; government: agent