１．Those want to take part in the sport meet, writedown their names.

熱心網友

Those who want to take part in the sport meeting, writedown their names.

熱心網友

Those who want to take part in the sport meet, writedown their names.

熱心網友

對了，定語從句少了個引導詞，those與want之間加上一個that或者who

熱心網友

正確答案：those who