"It may be very cold tomorrow" 这句话的来源是基于当前的天气预报，通过对明天天气的预测得出。
例句：
"It may be very cold tomorrow, so don't forget to bring a jacket." (明天可能会很冷，所以不要忘了带上夹克衫。)
"The forecast says it may be very cold tomorrow, I better get some firewood." (预报说明天可能会很冷，我最好去搞点柴火。)