The structure “快要/快/就要/要……了” indicates that something is going to happen. For example: yào xià yǔ le 。 要下雨了。It's going to rain. huǒ chē jiù yào lái le 。 火车就要来了。The train is coming. diàn yǐnɡ kuài kāi shǐ le 。 电影快开始了。The movie is about to begin. wǒ de shēnɡ rì kuài yào dào le 。 我的生日快要到了。My birthday is coming up. If there is an adverbial of time in the sentence, then only“就要.....了”can be used. For example: mínɡ tiān zú qiú bǐ sài jiù yào kāi shǐ le 。 明天足球比赛就要开始了。The football match will start tomorrow. xià ɡè xīnɡ qī wǒ men jiù yào kǎo shì le 。 下个星期我们就要考试了。We're going to have an exam next week. mínɡ nián dà wèi jiù yào huí měi ɡuó le 。 明年大卫就要回美国了。David will go back to America next year.