One very important difference between British and American English that Japanese people need to learn is how we number the floors of a building. Like in Japan, in America the ground level floor (地面と同じレベルの階) of a building is called the
Dates in English can be a little complicated (複雑). We write and say dates in different ways and there are also differences between British and American English. In the UK we usually say the day first and then the month.