to laugh very loudly or uncontrollably
笑得前仰后合
"The movie was so funny that we laughed our heads off."
"这部电影太搞笑了，以至于我们笑得前仰后合。"
a strong desire to travel and explore the world
to suddenly start talking about something unrelated
To be caught unprepared or embarrassed.
to do something very important that will be remembered
to make unrealistic plans or dreams
to have an extremely enjoyable time
