为什么在MySQL插入五条信息，运行只出现一条信息

select * from s1;
insert into s1 values
('0611101','王超','20','男');
('0611101','李勇','21','男');
('0631101','钱小平','20','男');
('0621101','张三','20','女');
('0631101','钟五','19','女');