英语翻译用中文翻译英语2条问题1,多少运动员参加了上一届奥运会2,请告诉所有的孩子都来参加这个游戏3,我父亲是18岁参军

1.How many athletes attended the last Olympics?（一般过去时）
2.Please tell all the children to participate in/join in this game.(join in+活动；join sb in+活动)
3.My father joined the army when he was 18 years old(at the age of 18). （一般过去时）
4.Do you know when she joined the Party?(宾语从句中用一般过去时)
5.How long have you been in the League(How long have you been a League member)?(本句是入团多久,要避免用短暂性动词join)
6.If anyone picks up the watch, please hand in.(Whoever picks up the watch should hand in.主语从句)