１．Those want to take part in the sport meet, writedown their names.
热心网友
Those who want to take part in the sport meeting, writedown their names.
热心网友
Those who want to take part in the sport meet, writedown their names.
热心网友
对了，定语从句少了个引导词，those与want之间加上一个that或者who
热心网友
正确答案：those who