a vicious circle

• n. (疾病等的)恶性循环；[逻]循环论证

a vicious circle的用法和样例：

例句

1. And then you have a vicious circle of more unemployment and fewer taxpayer to share the burden.
   那便会产生失业率越高、分担此负担的纳税人越少的恶性循环。
2. I need experience to get a job but without a job I can't get experience it's a vicious circle.
   我得有经验才能找到工作，可是没有工作我就无法获得经验--这真是个恶性循环。