夜空呈红色往往预兆第二天天气晴朗。

A red sky at night often indicates fine weather the next day.

《牛津词典》

帕米萨诺和罗梅蒂在7月29日同一天生日，这可是365分之1的小概率，考虑到闰年，可能更小；这是某种预兆吗？

In a 1-out-of-365 chance, or less considering leap year, Palmisano and Rometty share the same birthday, July 29th; is that an omen of some kind?

youdao

这时我已有好几个月没有她的消息了。有一天，毫无征兆的，他突然打来电话。

I hadn't heard from him in months, and then out of the blue he called.

youdao