People who support gun rights generally look to the second part of the Second Amendment,the part that says "the right of the people to keep and bear arms."
people who support gun rights是一个定语从句,修饰people
后面look to 是谓语 the second part of the Second Amendment是宾语
逗号后面是second part的同位语,解释说明second part的具体内容
翻译过来
支持持枪权的人们看到的主要是第二修正案的第二部分,里面说到：人们有权拥有与携带武器“