重点讲解：
1.by accident 偶然地；意外；不小心
例句：I found out the secret of the matter by accident.
我偶然发现了那件事情的秘密。

2.at random 随便地；随机地
例句：The children sat around the table at random.
小孩们随便的围坐在桌子旁边。

3.with the odds 可能性
例句：Even with the odds of detecting dark matter not in their favor, astrophysicists maintain an unwavering optimism.
对于天体物理学家们来说，尽管发现暗物质的可能性并不大，但他们一贯保持着乐观的态度。

4.grind to a halt 慢慢停下来；慢慢停止
例句：Every thirty seconds, the server experiences a huge storm of disk-writing activity, causing the system to nearly grind to a halt.
每隔30秒，服务器就会遇到磁盘写活动高峰，导致系统几乎陷于停顿。