碰巧听到：指在某个场合或时间，无意中听到某些信息或对话。
[魔鬼词典 ] 偷听 （ happen to hear ） 获取别人对你的公允评价的唯一途径。
偷听；恰巧听说；碰巧听到
I happen to hear the news.
我恰巧听说了这个消息。
Those who happen to hear it may suffer.
那些谁碰巧听到它可能受到影响。
If you happen to hear a humming sound and see a flash of color whiz by... who knows?
假如你偶然听到嗡嗡的声音并看见一道缤纷色彩色彩掠过…谁知道呢？
They want to see and hear for sure what's going to happen before they really even commit more money.
The New York Times reported Tuesday that bin Laden called his mother September 10 and told her "something big" was about to happen and that she would not hear from him for a long time.
One keeps wondering what's going to happen next, and when we might hear something about policy or electoral strategy.