滚雪球  (gǔn xuěqiú) snowball；increase or accumulate at a rapidly accelerating rate

Usage:

“滚雪球”本意是下雪时孩子们玩的一种游戏，就是把雪滚成越来越大的雪球。后来用来指事物在原来的基础上数量越来越多，规模越来越大。
“滚雪球”means a game kids play when it snow which is snowballing. later it’s referred that something has increased or accumulated at a rapidly accelerating rate.

Sentences:

1、Tā qiàn de zhài jiù xiàng gǔnxuěqiú yíyàng, zhè bèizi gūjì huánbùqīng le.
他欠的债就像滚雪球一样，这辈子估计还不清了。
He can not pay the debt in his life which has been snowballing now.

2、Zhè ge gōngsī gěi yuángōng de rènwù xiàng gǔnxuěqiú yíyàng, yuè lái yuè duō.
这个公司给员工的任务像滚雪球一样，越来越多。
The company gives the employees more and more assignments at a rapidly accelerating rate.

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