April 1 every year is April Fool's Day. It is the happiest day for the people in western countries.On April 1, you can tell a lie, make a joke to others, or cheat them, but they will not be angry with you.
每年4月1日是愚人节，它是西方国家人们最开心的日子。在4月1日，你可以跟别人说谎、开玩笑，或者骗他们，而他们并不与你生气。