1、fourth意思是第四，例如：“My birthday is on the fourth of December.”

2、fourth在比赛排名中也常用，例如：“Daniel was fourth in the race.”

3、在表示楼层时也可以使用，例如：“They took the lift to the fourth floor.”。当做形容词使用是“1/4”的意思，例如：“Three-fourth of the watermelon.”，“The fourths of his students, or 75%,come from the local area.”